diff --git a/adminfront/src/features/tenants/routes/TenantSchemaPage.tsx b/adminfront/src/features/tenants/routes/TenantSchemaPage.tsx
index c81854b7..17ff2bdf 100644
--- a/adminfront/src/features/tenants/routes/TenantSchemaPage.tsx
+++ b/adminfront/src/features/tenants/routes/TenantSchemaPage.tsx
@@ -34,6 +34,7 @@ type SchemaField = {
   adminOnly: boolean;
   validation?: string;
   unsigned?: boolean;
+  isLoginId?: boolean;
 };
 
 function createFieldId() {
@@ -96,6 +97,8 @@ export function TenantSchemaPage() {
 
   useEffect(() => {
     const rawSchema = tenantQuery.data?.config?.userSchema;
+    const loginIdField = tenantQuery.data?.config?.loginIdField;
+
     if (Array.isArray(rawSchema)) {
       setFields(
         rawSchema.map((field) => ({
@@ -115,19 +118,23 @@ export function TenantSchemaPage() {
           validation:
             typeof field?.validation === "string" ? field.validation : "",
           unsigned: Boolean(field?.unsigned),
+          isLoginId: field?.key === loginIdField,
         })),
       );
     }
   }, [tenantQuery.data]);
 
   const updateMutation = useMutation({
-    mutationFn: (newFields: SchemaField[]) =>
-      updateTenant(tenantId, {
+    mutationFn: (newFields: SchemaField[]) => {
+      const loginIdField = newFields.find((f) => f.isLoginId)?.key || "";
+      return updateTenant(tenantId, {
         config: {
           ...tenantQuery.data?.config,
           userSchema: newFields,
+          loginIdField: loginIdField,
         },
-      }),
+      });
+    },
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: ["tenant", tenantId] });
       toast.success(
@@ -334,6 +341,26 @@ export function TenantSchemaPage() {
                       )}
                     </span>
                   </label>
+                  <label className="flex items-center gap-2 cursor-pointer">
+                    <input
+                      type="checkbox"
+                      checked={field.isLoginId}
+                      onChange={(e) => {
+                        const newFields = fields.map((f, i) => ({
+                          ...f,
+                          isLoginId: i === index ? e.target.checked : false,
+                        }));
+                        setFields(newFields);
+                      }}
+                      className="w-4 h-4 rounded border-gray-300 text-primary focus:ring-primary"
+                    />
+                    <span className="text-sm font-medium text-blue-600">
+                      {t(
+                        "ui.admin.tenants.schema.field.is_login_id",
+                        "로그인 ID로 사용",
+                      )}
+                    </span>
+                  </label>
                   {(field.type === "number" || field.type === "float") && (
                     <label className="flex items-center gap-2 cursor-pointer">
                       <input
diff --git a/adminfront/src/features/users/UserCreatePage.tsx b/adminfront/src/features/users/UserCreatePage.tsx
index a29d6367..4b77d6a9 100644
--- a/adminfront/src/features/users/UserCreatePage.tsx
+++ b/adminfront/src/features/users/UserCreatePage.tsx
@@ -65,6 +65,7 @@ function UserCreatePage() {
   } = useForm<UserFormValues>({
     defaultValues: {
       email: "",
+      loginId: "",
       password: "",
       name: "",
       phone: "",
@@ -273,6 +274,26 @@ function UserCreatePage() {
               )}
             </div>
 
+            <div className="space-y-2">
+              <Label htmlFor="loginId">
+                {t("ui.admin.users.create.form.login_id", "로그인 ID (선택)")}
+              </Label>
+              <Input
+                id="loginId"
+                placeholder={t(
+                  "ui.admin.users.create.form.login_id_placeholder",
+                  "사번 또는 아이디",
+                )}
+                {...register("loginId")}
+              />
+              <p className="text-[10px] text-muted-foreground">
+                {t(
+                  "msg.admin.users.create.form.login_id_help",
+                  "이메일/전화번호 외에 별도의 식별자로 로그인할 때 사용합니다.",
+                )}
+              </p>
+            </div>
+
             <div className="space-y-2">
               <div className="flex items-center justify-between">
                 <Label htmlFor="password">
diff --git a/adminfront/src/features/users/UserDetailPage.tsx b/adminfront/src/features/users/UserDetailPage.tsx
index 506a5888..0f057712 100644
--- a/adminfront/src/features/users/UserDetailPage.tsx
+++ b/adminfront/src/features/users/UserDetailPage.tsx
@@ -5,20 +5,20 @@ import {
   BadgeCheck,
   Building2,
   Copy,
-  Dices,
-  Eye,
-  EyeOff,
+  Key,
   Loader2,
+  Mail,
+  RefreshCw,
   Save,
+  Trash2,
+  UserCheck,
+  UserMinus,
   Users,
 } from "lucide-react";
 import * as React from "react";
-import {
-  type FieldErrors,
-  type UseFormRegister,
-  useForm,
-} from "react-hook-form";
+import { useForm } from "react-hook-form";
 import { Link, useNavigate, useParams } from "react-router-dom";
+import { Badge } from "../../components/ui/badge";
 import { Button } from "../../components/ui/button";
 import {
   Card,
@@ -31,8 +31,9 @@ import { Input } from "../../components/ui/input";
 import { Label } from "../../components/ui/label";
 import { toast } from "../../components/ui/use-toast";
 import {
-  type TenantSummary,
+  type UserSummary,
   type UserUpdateRequest,
+  deleteUser,
   fetchMe,
   fetchTenant,
   fetchTenants,
@@ -40,19 +41,7 @@ import {
   updateUser,
 } from "../../lib/adminApi";
 import { t } from "../../lib/i18n";
-
-// Utility for secure password generation
-function generateSecurePassword(length = 16) {
-  const charset =
-    "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()_+~`|}{[]:;?><,./-=";
-  let retVal = "";
-  const values = new Uint32Array(length);
-  crypto.getRandomValues(values);
-  for (let i = 0; i < length; i++) {
-    retVal += charset.charAt(values[i] % charset.length);
-  }
-  return retVal;
-}
+import { generateSecurePassword } from "../../lib/utils";
 
 type UserSchemaField = {
   key: string;
@@ -60,40 +49,19 @@ type UserSchemaField = {
   type?: "text" | "number" | "boolean" | "date";
   required?: boolean;
   adminOnly?: boolean;
-  validation?: string;
 };
 
-type UserFormValues = UserUpdateRequest & {
-  metadata: Record<string, Record<string, unknown>>;
-};
-
-// [New] Component for per-tenant profile/schema management
-function TenantProfileCard({
+function TenantMetadataFields({
   tenant,
+  schema,
   register,
   errors,
-  isAdmin,
 }: {
-  tenant: TenantSummary;
-  register: UseFormRegister<UserFormValues>;
-  errors: FieldErrors<UserFormValues>;
-  isAdmin: boolean;
+  tenant: { id: string; name: string; slug: string };
+  schema: UserSchemaField[];
+  register: any;
+  errors: any;
 }) {
-  const { data: detail, isLoading } = useQuery({
-    queryKey: ["tenant", tenant.id],
-    queryFn: () => fetchTenant(tenant.id),
-  });
-
-  const schema: UserSchemaField[] = Array.isArray(detail?.config?.userSchema)
-    ? (detail?.config?.userSchema as UserSchemaField[])
-    : [];
-
-  if (isLoading)
-    return (
-      <div className="p-4 border rounded-lg animate-pulse bg-muted/20">
-        Loading schema...
-      </div>
-    );
   if (schema.length === 0) return null;
 
   return (
@@ -171,6 +139,8 @@ function TenantProfileCard({
   );
 }
 
+type UserFormValues = UserUpdateRequest & { metadata: Record<string, any> };
+
 function UserDetailPage() {
   const params = useParams<{ id: string }>();
   const userId = params.id ?? "";
@@ -210,6 +180,7 @@ function UserDetailPage() {
     formState: { errors },
   } = useForm<UserFormValues>({
     defaultValues: {
+      loginId: "",
       name: "",
       phone: "",
       role: "user",
@@ -251,6 +222,7 @@ function UserDetailPage() {
   React.useEffect(() => {
     if (user) {
       reset({
+        loginId: user.loginId || "",
         name: user.name,
         phone: user.phone || "",
         role: user.role,
@@ -259,11 +231,7 @@ function UserDetailPage() {
         department: user.department || "",
         position: user.position || "",
         jobTitle: user.jobTitle || "",
-        password: "",
-        metadata: (user.metadata || {}) as unknown as Record<
-          string,
-          Record<string, unknown>
-        >,
+        metadata: user.metadata || {},
       });
     }
   }, [user, reset]);
@@ -279,404 +247,500 @@ function UserDetailPage() {
           "사용자 정보가 수정되었습니다.",
         ),
       );
-      setError(null);
+      toast.success(
+        t(
+          "msg.admin.users.detail.update_success",
+          "사용자 정보가 수정되었습니다.",
+        ),
+      );
+      setTimeout(() => setSuccessMsg(null), 3000);
     },
     onError: (err: AxiosError<{ error?: string }>) => {
       setError(
         err.response?.data?.error ||
-          t(
-            "msg.admin.users.detail.update_error",
-            "사용자 수정에 실패했습니다.",
-          ),
+          t("msg.admin.users.detail.update_error", "수정에 실패했습니다."),
+      );
+    },
+  });
+
+  const deleteMutation = useMutation({
+    mutationFn: () => deleteUser(userId),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ["users"] });
+      toast.success(
+        t("msg.admin.users.detail.delete_success", "사용자가 삭제되었습니다."),
+      );
+      navigate("/users");
+    },
+    onError: (err: AxiosError<{ error?: string }>) => {
+      toast.error(
+        err.response?.data?.error ||
+          t("msg.admin.users.detail.delete_error", "삭제에 실패했습니다."),
       );
-      setSuccessMsg(null);
     },
   });
 
   const onSubmit = (data: UserFormValues) => {
-    const payload: UserUpdateRequest = { ...data };
-    if (!payload.password) {
-      payload.password = undefined;
+    setError(null);
+    setSuccessMsg(null);
+    mutation.mutate(data);
+  };
+
+  const handleDelete = () => {
+    if (
+      window.confirm(
+        t(
+          "msg.admin.users.detail.delete_confirm",
+          "정말로 이 사용자를 삭제하시겠습니까? 이 작업은 되돌릴 수 없습니다.",
+        ),
+      )
+    ) {
+      deleteMutation.mutate();
     }
-    mutation.mutate(payload);
   };
 
   if (isLoading) {
     return (
-      <div className="p-8 text-center">
-        {t("msg.common.loading", "Loading...")}
+      <div className="flex h-64 items-center justify-center">
+        <Loader2 className="h-8 w-8 animate-spin text-primary" />
       </div>
     );
   }
 
   if (isError || !user) {
     return (
-      <div className="p-8 text-center text-destructive">
-        {t("msg.admin.users.detail.not_found", "사용자를 찾을 수 없습니다.")}
+      <div className="rounded-md bg-destructive/15 p-6 text-center">
+        <p className="text-destructive">
+          {t("msg.admin.users.detail.not_found", "사용자를 찾을 수 없습니다.")}
+        </p>
+        <Button
+          variant="outline"
+          className="mt-4"
+          onClick={() => navigate("/users")}
+        >
+          {t("ui.admin.users.detail.go_list", "목록으로 이동")}
+        </Button>
       </div>
     );
   }
 
-  // Combined affiliated tenants
-  const userAffiliatedTenants = [...(user.joinedTenants || [])];
-  if (
-    user.tenant &&
-    !userAffiliatedTenants.find((t) => t.id === user.tenant?.id)
-  ) {
-    userAffiliatedTenants.push(user.tenant);
-  }
+  // Get only tenants that the user is actually affiliated with
+  const userAffiliatedTenants =
+    user.joinedTenants || (user.tenant ? [user.tenant] : []);
 
   return (
-    <div className="max-w-3xl space-y-8">
-      <header className="flex flex-wrap items-center justify-between gap-4">
-        <div className="space-y-2">
-          <h2 className="text-3xl font-semibold">
-            {t("ui.admin.users.detail.title", "사용자 상세")}
-          </h2>
-        </div>
-        <Button variant="ghost" asChild>
-          <Link to="/users">
-            <ArrowLeft size={16} className="mr-2" />
-            {t("ui.admin.users.detail.back", "목록으로 돌아가기")}
-          </Link>
+    <div className="space-y-6">
+      <div className="flex items-center justify-between">
+        <Button variant="ghost" onClick={() => navigate("/users")} size="sm">
+          <ArrowLeft className="mr-2 h-4 w-4" />
+          {t("ui.admin.users.detail.back", "목록으로")}
         </Button>
-      </header>
+        <div className="flex gap-2">
+          {isAdmin && (
+            <Button variant="destructive" onClick={handleDelete} size="sm">
+              <Trash2 className="mr-2 h-4 w-4" />
+              {t("ui.admin.users.detail.delete", "사용자 삭제")}
+            </Button>
+          )}
+        </div>
+      </div>
 
-      <Card>
-        <CardHeader>
-          <CardTitle>
-            {t("ui.admin.users.detail.edit_title", "정보 수정")}
-          </CardTitle>
-          <CardDescription>
-            {t(
-              "msg.admin.users.detail.edit_subtitle",
-              "{{email}} 계정의 정보를 수정합니다.",
-              { email: user.email },
-            )}
-          </CardDescription>
-        </CardHeader>
-        <CardContent>
-          <form onSubmit={handleSubmit(onSubmit)} className="space-y-6">
-            {error && (
-              <div className="rounded-md bg-destructive/15 p-3 text-sm text-destructive">
-                {error}
-              </div>
-            )}
-            {successMsg && (
-              <div className="rounded-md bg-green-500/15 p-3 text-sm text-green-500">
-                {successMsg}
-              </div>
-            )}
-
-            {/* Tenant Affiliation Section (Enhanced) */}
-            <div className="rounded-lg border border-border bg-muted/30 p-4 space-y-4">
-              <h3 className="text-sm font-semibold flex items-center gap-2">
-                <Building2 size={16} className="text-primary" />
+      <div className="grid gap-6 lg:grid-cols-3">
+        <div className="lg:col-span-2 space-y-6">
+          <Card>
+            <CardHeader>
+              <CardTitle>
+                {t("ui.admin.users.detail.edit_title", "사용자 정보 수정")}
+              </CardTitle>
+              <CardDescription>
                 {t(
-                  "ui.admin.users.detail.tenants_section.title",
-                  "소속 및 조직 정보",
+                  "msg.admin.users.detail.edit_subtitle",
+                  "{{email}} 계정의 정보를 수정합니다.",
+                  { email: user.email },
+                )}
+              </CardDescription>
+            </CardHeader>
+            <CardContent>
+              <form onSubmit={handleSubmit(onSubmit)} className="space-y-6">
+                {error && (
+                  <div className="rounded-md bg-destructive/15 p-3 text-sm text-destructive">
+                    {error}
+                  </div>
+                )}
+                {successMsg && (
+                  <div className="rounded-md bg-green-500/15 p-3 text-sm text-green-500">
+                    {successMsg}
+                  </div>
                 )}
-              </h3>
 
-              <div className="grid gap-6 md:grid-cols-2">
-                <div className="space-y-2">
-                  <Label className="text-[10px] uppercase text-muted-foreground tracking-wider font-bold">
+                {/* Tenant Affiliation Section (Enhanced) */}
+                <div className="rounded-lg border border-border bg-muted/30 p-4 space-y-4">
+                  <h3 className="text-sm font-semibold flex items-center gap-2">
+                    <Building2 size={16} className="text-primary" />
                     {t(
-                      "ui.admin.users.detail.tenants_section.primary",
-                      "대표 소속 테넌트",
+                      "ui.admin.users.detail.tenants_section.title",
+                      "소속 및 조직 정보",
                     )}
-                  </Label>
+                  </h3>
 
-                  {/* Select box to specify representative tenant from joined ones */}
-                  {userAffiliatedTenants.length > 0 ? (
-                    <div className="relative">
-                      <select
-                        className="flex h-10 w-full rounded-md border border-input bg-background px-3 py-2 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary disabled:opacity-50"
-                        {...register("tenantSlug")}
-                        disabled={
-                          profile?.role === "tenant_admin" &&
-                          userAffiliatedTenants.length <= 1
-                        }
-                      >
-                        <option value="">
+                  <div className="grid gap-6 md:grid-cols-2">
+                    <div className="space-y-2">
+                      <Label className="text-[10px] uppercase text-muted-foreground tracking-wider font-bold">
+                        {t(
+                          "ui.admin.users.detail.tenants_section.primary",
+                          "대표 소속 테넌트",
+                        )}
+                      </Label>
+
+                      {/* Select box to specify representative tenant from joined ones */}
+                      {userAffiliatedTenants.length > 0 ? (
+                        <div className="relative">
+                          <select
+                            className="flex h-10 w-full rounded-md border border-input bg-background px-3 py-2 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary disabled:opacity-50"
+                            {...register("tenantSlug")}
+                            disabled={
+                              profile?.role === "tenant_admin" &&
+                              userAffiliatedTenants.length <= 1
+                            }
+                          >
+                            <option value="">
+                              {t(
+                                "ui.admin.users.detail.form.tenant_global",
+                                "시스템 전역",
+                              )}
+                            </option>
+                            {userAffiliatedTenants.map((t) => (
+                              <option key={t.id} value={t.slug}>
+                                {t.name} ({t.slug})
+                              </option>
+                            ))}
+                          </select>
+                          <BadgeCheck
+                            size={14}
+                            className="absolute right-8 top-3 text-primary pointer-events-none"
+                          />
+                        </div>
+                      ) : (
+                        <div className="flex items-center gap-2 p-2 rounded-md bg-background border border-dashed border-border text-muted-foreground italic text-xs">
                           {t(
                             "ui.admin.users.detail.form.tenant_global",
-                            "시스템 전역",
+                            "시스템 전역 (소속 없음)",
                           )}
-                        </option>
-                        {userAffiliatedTenants.map((t) => (
-                          <option key={t.id} value={t.slug}>
-                            {t.name} ({t.slug})
-                          </option>
-                        ))}
-                      </select>
-                      <BadgeCheck
-                        size={14}
-                        className="absolute right-8 top-3 text-primary pointer-events-none"
-                      />
-                    </div>
-                  ) : (
-                    <div className="flex items-center gap-2 p-2 rounded-md bg-background border border-dashed border-border text-muted-foreground italic text-xs">
-                      {t(
-                        "ui.admin.users.detail.form.tenant_global",
-                        "시스템 전역 (소속 없음)",
+                        </div>
                       )}
+                      <p className="text-[10px] text-muted-foreground">
+                        * 사용자의 주된 정체성을 결정하는 대표 조직을 선택합니다.
+                      </p>
                     </div>
-                  )}
-                  <p className="text-[10px] text-muted-foreground">
-                    * 사용자의 주된 정체성을 결정하는 대표 조직을 선택합니다.
-                  </p>
-                </div>
 
-                {userAffiliatedTenants.length > 1 && (
-                  <div className="space-y-1">
-                    <Label className="text-[10px] uppercase text-muted-foreground tracking-wider font-bold">
-                      {t(
-                        "ui.admin.users.detail.tenants_section.additional",
-                        "전체 소속 목록",
-                      )}
-                    </Label>
-                    <div className="flex flex-wrap gap-1.5 pt-1">
-                      {userAffiliatedTenants.map((jt) => (
-                        <Link
-                          key={jt.id}
-                          to={`/tenants/${jt.id}`}
-                          className={`inline-flex items-center gap-1 px-2 py-0.5 rounded border text-[11px] transition-colors ${
-                            jt.id ===
-                            tenants.find((t) => t.slug === watch("tenantSlug"))
-                              ?.id
-                              ? "bg-primary/10 border-primary/30 text-primary font-bold"
-                              : "bg-background border-border text-muted-foreground hover:border-primary/50"
-                          }`}
-                        >
-                          <Users size={10} />
-                          {jt.name}
-                        </Link>
-                      ))}
-                    </div>
-                  </div>
-                )}
-              </div>
-            </div>
-
-            <div className="grid gap-4 md:grid-cols-2">
-              <div className="space-y-2">
-                <Label htmlFor="name">
-                  {t("ui.admin.users.detail.form.name", "이름")}
-                </Label>
-                <Input
-                  id="name"
-                  placeholder={t(
-                    "ui.admin.users.detail.form.name_placeholder",
-                    "홍길동",
-                  )}
-                  {...register("name", {
-                    required: t(
-                      "msg.admin.users.detail.form.name_required",
-                      "이름은 필수입니다.",
-                    ),
-                  })}
-                />
-                {errors.name && (
-                  <p className="text-xs text-destructive">
-                    {errors.name.message}
-                  </p>
-                )}
-              </div>
-
-              <div className="space-y-2">
-                <Label htmlFor="phone">
-                  {t("ui.admin.users.detail.form.phone", "전화번호")}
-                </Label>
-                <Input
-                  id="phone"
-                  placeholder={t(
-                    "ui.admin.users.detail.form.phone_placeholder",
-                    "010-1234-5678",
-                  )}
-                  {...register("phone")}
-                />
-              </div>
-            </div>
-
-            <div className="grid gap-4 md:grid-cols-2">
-              <div className="space-y-2">
-                <Label htmlFor="status">
-                  {t("ui.admin.users.detail.form.status", "상태")}
-                </Label>
-                <div className="relative">
-                  <select
-                    id="status"
-                    className="flex h-9 w-full rounded-md border border-input bg-transparent px-3 py-1 text-sm shadow-sm transition-colors file:border-0 file:bg-transparent file:text-sm file:font-medium placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:cursor-not-allowed disabled:opacity-50"
-                    {...register("status")}
-                  >
-                    <option value="active">
-                      {t("ui.common.status.active", "Active")}
-                    </option>
-                    <option value="inactive">
-                      {t("ui.common.status.inactive", "Inactive")}
-                    </option>
-                    <option value="blocked">
-                      {t("ui.common.status.blocked", "Blocked")}
-                    </option>
-                  </select>
-                </div>
-              </div>
-
-              <div className="space-y-2">
-                <Label htmlFor="role">
-                  {t("ui.admin.users.detail.form.role", "역할 (Role)")}
-                </Label>
-                <div className="relative">
-                  <select
-                    id="role"
-                    className="flex h-9 w-full rounded-md border border-input bg-transparent px-3 py-1 text-sm shadow-sm transition-colors file:border-0 file:bg-transparent file:text-sm file:font-medium placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:cursor-not-allowed disabled:opacity-50"
-                    {...register("role")}
-                  >
-                    <option value="user">
-                      {t("ui.admin.role.user", "TENANT MEMBER")}
-                    </option>
-                    <option value="tenant_admin">
-                      {t("ui.admin.role.tenant_admin", "TENANT ADMIN")}
-                    </option>
-                    <option value="rp_admin">
-                      {t("ui.admin.role.rp_admin", "RP ADMIN")}
-                    </option>
-                    <option value="super_admin">
-                      {t("ui.admin.role.super_admin", "SUPER ADMIN")}
-                    </option>
-                  </select>
-                </div>
-              </div>
-            </div>
-
-            <div className="grid gap-4 md:grid-cols-2">
-              <div className="space-y-2">
-                <Label htmlFor="department">
-                  {t("ui.admin.users.detail.form.department", "부서")}
-                </Label>
-
-                <Input
-                  id="department"
-                  placeholder={t(
-                    "ui.admin.users.detail.form.department_placeholder",
-                    "개발팀",
-                  )}
-                  {...register("department")}
-                />
-              </div>
-            </div>
-
-            {/* Tenant-specific Profiles (Namespaced Metadata) */}
-            <div className="border-t pt-6 space-y-6">
-              <div className="flex flex-col gap-1">
-                <h3 className="text-sm font-bold text-muted-foreground uppercase tracking-wider">
-                  {t(
-                    "ui.admin.users.detail.custom_fields.multi_title",
-                    "테넌트별 프로필 관리",
-                  )}
-                </h3>
-                <p className="text-[11px] text-muted-foreground">
-                  사용자가 소속된 각 테넌트별 맞춤 정보를 관리합니다.
-                </p>
-              </div>
-
-              <div className="grid gap-4">
-                {userAffiliatedTenants.map((tenant) => (
-                  <TenantProfileCard
-                    key={tenant.id}
-                    tenant={tenant}
-                    register={register}
-                    errors={errors}
-                    isAdmin={isAdmin}
-                  />
-                ))}
-              </div>
-            </div>
-
-            <div className="border-t pt-4">
-              <h3 className="mb-4 text-sm font-medium text-muted-foreground">
-                {t("ui.admin.users.detail.security.title", "보안 설정")}
-              </h3>
-
-              <div className="space-y-2">
-                <Label htmlFor="password">
-                  {t(
-                    "ui.admin.users.detail.security.password",
-                    "비밀번호 변경",
-                  )}
-                </Label>
-                <div className="flex gap-2">
-                  <div className="relative flex-1">
-                    <Input
-                      id="password"
-                      type={showPassword ? "text" : "password"}
-                      placeholder={t(
-                        "ui.admin.users.detail.security.password_placeholder",
-                        "변경할 경우에만 입력",
-                      )}
-                      className="font-mono"
-                      {...register("password")}
-                    />
-                    <button
-                      type="button"
-                      onClick={() => setShowPassword(!showPassword)}
-                      className="absolute right-3 top-1/2 -translate-y-1/2 text-muted-foreground hover:text-foreground"
-                    >
-                      {showPassword ? <EyeOff size={16} /> : <Eye size={16} />}
-                    </button>
-                  </div>
-                  <Button
-                    type="button"
-                    variant="outline"
-                    onClick={handleGeneratePassword}
-                    title={t(
-                      "ui.admin.users.detail.generate_password",
-                      "자동 생성",
+                    {userAffiliatedTenants.length > 1 && (
+                      <div className="space-y-1">
+                        <Label className="text-[10px] uppercase text-muted-foreground tracking-wider font-bold">
+                          {t(
+                            "ui.admin.users.detail.tenants_section.additional",
+                            "전체 소속 목록",
+                          )}
+                        </Label>
+                        <div className="flex flex-wrap gap-1.5 pt-1">
+                          {userAffiliatedTenants.map((jt) => (
+                            <Link
+                              key={jt.id}
+                              to={`/tenants/${jt.id}`}
+                              className={`inline-flex items-center gap-1 px-2 py-0.5 rounded border text-[11px] transition-colors ${
+                                jt.id ===
+                                tenants.find(
+                                  (t) => t.slug === watch("tenantSlug"),
+                                )?.id
+                                  ? "bg-primary/10 border-primary/30 text-primary font-bold"
+                                  : "bg-background border-border text-muted-foreground hover:border-primary/50"
+                              }`}
+                            >
+                              <Users size={10} />
+                              {jt.name}
+                            </Link>
+                          ))}
+                        </div>
+                      </div>
                     )}
-                  >
-                    <Dices size={16} className="mr-2" />
-                    {t("ui.common.generate", "생성")}
-                  </Button>
-                  <Button
-                    type="button"
-                    variant="outline"
-                    size="icon"
-                    onClick={handleCopyPassword}
-                    disabled={!watch("password")}
-                    title={t("ui.common.copy", "복사")}
-                  >
-                    <Copy size={16} />
+                  </div>
+                </div>
+
+                <div className="grid gap-4 md:grid-cols-2">
+                  <div className="space-y-2">
+                    <Label htmlFor="name">
+                      {t("ui.admin.users.detail.form.name", "이름")}
+                    </Label>
+                    <Input
+                      id="name"
+                      placeholder={t(
+                        "ui.admin.users.detail.form.name_placeholder",
+                        "홍길동",
+                      )}
+                      {...register("name", {
+                        required: t(
+                          "msg.admin.users.detail.form.name_required",
+                          "이름은 필수입니다.",
+                        ),
+                      })}
+                    />
+                    {errors.name && (
+                      <p className="text-xs text-destructive">
+                        {errors.name.message}
+                      </p>
+                    )}
+                  </div>
+
+                  <div className="space-y-2">
+                    <Label htmlFor="phone">
+                      {t("ui.admin.users.detail.form.phone", "전화번호")}
+                    </Label>
+                    <Input
+                      id="phone"
+                      placeholder={t(
+                        "ui.admin.users.detail.form.phone_placeholder",
+                        "010-1234-5678",
+                      )}
+                      {...register("phone")}
+                    />
+                  </div>
+                </div>
+
+                <div className="space-y-2">
+                  <Label htmlFor="loginId">
+                    {t("ui.admin.users.detail.form.login_id", "로그인 ID")}
+                  </Label>
+                  <Input
+                    id="loginId"
+                    placeholder={t(
+                      "ui.admin.users.detail.form.login_id_placeholder",
+                      "사번 또는 아이디",
+                    )}
+                    {...register("loginId")}
+                  />
+                </div>
+
+                <div className="grid gap-4 md:grid-cols-2">
+                  <div className="space-y-2">
+                    <Label htmlFor="role">
+                      {t("ui.admin.users.detail.form.role", "권한")}
+                    </Label>
+                    <select
+                      id="role"
+                      className="flex h-10 w-full rounded-md border border-input bg-background px-3 py-2 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary disabled:opacity-50"
+                      {...register("role")}
+                    >
+                      <option value="user">
+                        {t("ui.admin.users.detail.form.role_user", "일반 사용자")}
+                      </option>
+                      <option value="tenant_admin">
+                        {t(
+                          "ui.admin.users.detail.form.role_tenant_admin",
+                          "테넌트 관리자",
+                        )}
+                      </option>
+                      <option value="super_admin">
+                        {t(
+                          "ui.admin.users.detail.form.role_super_admin",
+                          "시스템 관리자",
+                        )}
+                      </option>
+                    </select>
+                  </div>
+
+                  <div className="space-y-2">
+                    <Label htmlFor="status">
+                      {t("ui.admin.users.detail.form.status", "상태")}
+                    </Label>
+                    <select
+                      id="status"
+                      className="flex h-10 w-full rounded-md border border-input bg-background px-3 py-2 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary disabled:opacity-50"
+                      {...register("status")}
+                    >
+                      <option value="active">
+                        {t("ui.admin.users.detail.form.status_active", "활성")}
+                      </option>
+                      <option value="inactive">
+                        {t("ui.admin.users.detail.form.status_inactive", "비활성")}
+                      </option>
+                    </select>
+                  </div>
+                </div>
+
+                <div className="grid gap-4 md:grid-cols-2">
+                  <div className="space-y-2">
+                    <Label htmlFor="department">
+                      {t("ui.admin.users.detail.form.department", "부서")}
+                    </Label>
+                    <Input
+                      id="department"
+                      placeholder={t(
+                        "ui.admin.users.detail.form.department_placeholder",
+                        "개발팀",
+                      )}
+                      {...register("department")}
+                    />
+                  </div>
+                  <div className="space-y-2">
+                    <Label htmlFor="position">
+                      {t("ui.admin.users.detail.form.position", "직급")}
+                    </Label>
+                    <Input
+                      id="position"
+                      placeholder={t(
+                        "ui.admin.users.detail.form.position_placeholder",
+                        "수석",
+                      )}
+                      {...register("position")}
+                    />
+                  </div>
+                </div>
+
+                <div className="space-y-2">
+                  <Label htmlFor="jobTitle">
+                    {t("ui.admin.users.detail.form.job_title", "직무")}
+                  </Label>
+                  <Input
+                    id="jobTitle"
+                    placeholder={t(
+                      "ui.admin.users.detail.form.job_title_placeholder",
+                      "백엔드 개발",
+                    )}
+                    {...register("jobTitle")}
+                  />
+                </div>
+
+                <div className="space-y-4">
+                  <div className="flex items-center justify-between">
+                    <Label>{t("ui.admin.users.detail.metadata", "추가 정보")}</Label>
+                  </div>
+                  <div className="grid gap-4">
+                    {userAffiliatedTenants.map((t) => {
+                      const tDetail = tenants.find((tenant) => tenant.id === t.id);
+                      const schema = (tDetail?.config?.userSchema ||
+                        []) as UserSchemaField[];
+                      return (
+                        <TenantMetadataFields
+                          key={t.id}
+                          tenant={t}
+                          schema={schema}
+                          register={register}
+                          errors={errors}
+                        />
+                      );
+                    })}
+                  </div>
+                </div>
+
+                <div className="flex justify-end pt-4">
+                  <Button type="submit" disabled={mutation.isPending}>
+                    {mutation.isPending && (
+                      <Loader2 className="mr-2 h-4 w-4 animate-spin" />
+                    )}
+                    <Save className="mr-2 h-4 w-4" />
+                    {t("ui.admin.users.detail.save", "변경사항 저장")}
                   </Button>
                 </div>
-                <p className="text-xs text-muted-foreground">
-                  {t(
-                    "msg.admin.users.detail.security.password_hint",
-                    "비밀번호를 변경하려면 입력하세요. 비워두면 현재 비밀번호가 유지됩니다.",
-                  )}
-                </p>
-              </div>
-            </div>
+              </form>
+            </CardContent>
+          </Card>
 
-            <div className="flex justify-end gap-4">
-              <Button
-                type="button"
-                variant="outline"
-                onClick={() => navigate("/users")}
-              >
-                {t("ui.common.cancel", "취소")}
-              </Button>
-              <Button type="submit" disabled={mutation.isPending}>
-                {mutation.isPending && (
-                  <Loader2 className="mr-2 h-4 w-4 animate-spin" />
-                )}
-                <Save className="mr-2 h-4 w-4" />
-                {t("ui.common.save", "저장")}
-              </Button>
-            </div>
-          </form>
-        </CardContent>
-      </Card>
+          <Card>
+            <CardHeader>
+              <CardTitle className="text-lg flex items-center gap-2">
+                <Key size={18} />
+                {t("ui.admin.users.detail.password_title", "비밀번호 관리")}
+              </CardTitle>
+            </CardHeader>
+            <CardContent className="space-y-4">
+              <div className="flex items-center justify-between p-4 border rounded-lg bg-muted/20">
+                <div className="space-y-1">
+                  <p className="text-sm font-medium">
+                    {t(
+                      "ui.admin.users.detail.reset_password_label",
+                      "비밀번호 초기화",
+                    )}
+                  </p>
+                  <p className="text-xs text-muted-foreground">
+                    사용자의 비밀번호를 강제로 재설정하고 새 비밀번호를 생성합니다.
+                  </p>
+                </div>
+                <Button variant="outline" onClick={handleGeneratePassword}>
+                  <RefreshCw className="mr-2 h-4 w-4" />
+                  {t("ui.admin.users.detail.reset_password", "초기화 및 생성")}
+                </Button>
+              </div>
+
+              {showPassword && (
+                <div className="p-4 border border-dashed rounded-lg bg-yellow-500/5 flex flex-wrap items-center justify-between gap-4">
+                  <div className="space-y-1">
+                    <p className="text-xs font-bold text-yellow-600 uppercase tracking-wider">
+                      Generated Password
+                    </p>
+                    <p className="font-mono text-lg font-bold">
+                      {watch("password")}
+                    </p>
+                  </div>
+                  <Button size="sm" variant="secondary" onClick={handleCopyPassword}>
+                    <Copy className="mr-2 h-4 w-4" />
+                    {t("ui.common.copy", "복사")}
+                  </Button>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+        </div>
+
+        <div className="space-y-6">
+          <Card>
+            <CardHeader>
+              <CardTitle className="text-lg">
+                {t("ui.admin.users.detail.status_title", "계정 상태")}
+              </CardTitle>
+            </CardHeader>
+            <CardContent className="space-y-4">
+              <div className="flex items-center gap-4">
+                <div className="h-12 w-12 rounded-full bg-primary/10 flex items-center justify-center text-primary">
+                  <UserCheck size={24} />
+                </div>
+                <div>
+                  <div className="flex items-center gap-2">
+                    <Badge variant={user.status === "active" ? "default" : "secondary"}>
+                      {user.status === "active" ? "Active" : "Inactive"}
+                    </Badge>
+                    <Badge variant="outline">{user.role}</Badge>
+                  </div>
+                  <p className="text-xs text-muted-foreground mt-1">
+                    {t("ui.admin.users.detail.created_at", "가입일")}:{" "}
+                    {new Date(user.createdAt).toLocaleDateString()}
+                  </p>
+                </div>
+              </div>
+            </CardContent>
+          </Card>
+
+          <Card>
+            <CardHeader>
+              <CardTitle className="text-lg">
+                {t("ui.admin.users.detail.contact_title", "연락처 정보")}
+              </CardTitle>
+            </CardHeader>
+            <CardContent className="space-y-3">
+              <div className="flex items-center gap-2 text-sm">
+                <Mail size={14} className="text-muted-foreground" />
+                <span>{user.email}</span>
+              </div>
+              {user.phone && (
+                <div className="flex items-center gap-2 text-sm">
+                  <Badge variant="outline" className="font-normal">
+                    SMS
+                  </Badge>
+                  <span>{user.phone}</span>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+        </div>
+      </div>
     </div>
   );
 }
diff --git a/adminfront/src/features/users/UserListPage.tsx b/adminfront/src/features/users/UserListPage.tsx
index dffb6349..573f8861 100644
--- a/adminfront/src/features/users/UserListPage.tsx
+++ b/adminfront/src/features/users/UserListPage.tsx
@@ -430,6 +430,9 @@ function UserListPage() {
                         "NAME / EMAIL",
                       )}
                     </TableHead>
+                    <TableHead>
+                      {t("ui.admin.users.list.table.login_id", "LOGIN ID")}
+                    </TableHead>
                     <TableHead>
                       {t("ui.admin.users.list.table.role", "ROLE")}
                     </TableHead>
@@ -511,6 +514,11 @@ function UserListPage() {
                           </div>
                         </div>
                       </TableCell>
+                      <TableCell>
+                        <span className="text-sm font-mono">
+                          {user.loginId || "-"}
+                        </span>
+                      </TableCell>
                       <TableCell>
                         <Badge variant="outline">
                           {t(`ui.admin.role.${user.role}`, user.role)}
diff --git a/adminfront/src/lib/adminApi.ts b/adminfront/src/lib/adminApi.ts
index 5ebeca3e..aa8d52ab 100644
--- a/adminfront/src/lib/adminApi.ts
+++ b/adminfront/src/lib/adminApi.ts
@@ -348,6 +348,7 @@ export async function deleteApiKey(apiKeyId: string) {
 export type UserSummary = {
   id: string;
   email: string;
+  loginId?: string;
   name: string;
   phone?: string;
   role: string;
@@ -372,6 +373,7 @@ export type UserListResponse = {
 
 export type UserCreateRequest = {
   email: string;
+  loginId?: string;
   password?: string;
   name: string;
   phone?: string;
@@ -388,6 +390,7 @@ export type UserCreateResponse = UserSummary & {
 };
 
 export type UserUpdateRequest = {
+  loginId?: string;
   password?: string;
   name?: string;
   phone?: string;
@@ -402,6 +405,7 @@ export type UserUpdateRequest = {
 
 export type BulkUserItem = {
   email: string;
+  loginId?: string;
   name: string;
   phone?: string;
   role?: string;
diff --git a/backend/internal/domain/auth_models.go b/backend/internal/domain/auth_models.go
index f947413c..8167ce35 100644
--- a/backend/internal/domain/auth_models.go
+++ b/backend/internal/domain/auth_models.go
@@ -55,6 +55,7 @@ type VerifySignupCodeRequest struct {
 
 type SignupRequest struct {
 	Email           string  `json:"email"`
+	LoginID         string  `json:"loginId,omitempty"`
 	Password        string  `json:"password"`
 	Name            string  `json:"name"`
 	Phone           string  `json:"phone"`
@@ -70,6 +71,7 @@ type SignupRequest struct {
 type UserProfileResponse struct {
 	ID                     string         `json:"id"`
 	Email                  string         `json:"email"`
+	LoginID                string         `json:"loginId,omitempty"`
 	Name                   string         `json:"name"`
 	Phone                  string         `json:"phone"`
 	Role                   string         `json:"role"` // 추가
diff --git a/backend/internal/domain/idp_models.go b/backend/internal/domain/idp_models.go
index 43aadec3..6cbbe208 100644
--- a/backend/internal/domain/idp_models.go
+++ b/backend/internal/domain/idp_models.go
@@ -14,6 +14,7 @@ var ErrNotSupported = errors.New("idp: not supported")
 type BrokerUser struct {
 	ID          string `json:"id" required:"true"`
 	Email       string `json:"email" required:"true"`
+	LoginID     string `json:"login_id"`
 	Name        string `json:"name"`
 	PhoneNumber string `json:"phone_number"`
 	// Attributes stores custom user attributes.
diff --git a/backend/internal/domain/user.go b/backend/internal/domain/user.go
index 448f116e..411f3aa7 100644
--- a/backend/internal/domain/user.go
+++ b/backend/internal/domain/user.go
@@ -34,13 +34,14 @@ func NormalizeRole(role string) string {
 type User struct {
 	ID              string         `gorm:"primaryKey;type:uuid;default:gen_random_uuid()" json:"id"`
 	Email           string         `gorm:"uniqueIndex;not null" json:"email"`
+	LoginID         string         `gorm:"column:login_id;uniqueIndex:idx_tenant_login_id" json:"loginId"`
 	PasswordHash    *string        `gorm:"column:password_hash" json:"-"`
 	Name            string         `gorm:"column:name;not null" json:"name"`
 	Phone           string         `gorm:"column:phone" json:"phone"`
 	Role            string         `gorm:"column:role;default:'user';not null" json:"role"` // super_admin, tenant_admin, rp_admin, user
 	AffiliationType string         `gorm:"column:affiliation_type" json:"affiliationType"`
 	CompanyCode     string         `gorm:"column:company_code;index" json:"companyCode"`
-	TenantID        *string        `gorm:"column:tenant_id;type:uuid;index" json:"tenantId,omitempty"`
+	TenantID        *string        `gorm:"column:tenant_id;type:uuid;index;uniqueIndex:idx_tenant_login_id" json:"tenantId,omitempty"`
 	Tenant          *Tenant        `gorm:"foreignKey:TenantID" json:"tenant,omitempty"`
 	RelyingPartyID  *string        `gorm:"column:relying_party_id;type:uuid;index" json:"relyingPartyId,omitempty"` // RP Admin용
 	Department      string         `gorm:"column:department" json:"department"`
diff --git a/backend/internal/handler/auth_handler.go b/backend/internal/handler/auth_handler.go
index 5b6b98ae..dcae0d06 100644
--- a/backend/internal/handler/auth_handler.go
+++ b/backend/internal/handler/auth_handler.go
@@ -577,14 +577,31 @@ func (h *AuthHandler) GetTenantInfo(c *fiber.Ctx) error {
 		return errorJSON(c, fiber.StatusNotFound, "Tenant not found")
 	}
 
-	return c.JSON(fiber.Map{
+	res := fiber.Map{
 		"isCentral":   false,
 		"id":          tenant.ID,
 		"name":        tenant.Name,
 		"slug":        tenant.Slug,
 		"description": tenant.Description,
 		"type":        tenant.Type,
-	})
+	}
+
+	if loginIdField, ok := tenant.Config["loginIdField"].(string); ok && loginIdField != "" {
+		res["loginIdField"] = loginIdField
+		// Find label in userSchema
+		if schema, ok := tenant.Config["userSchema"].([]interface{}); ok {
+			for _, field := range schema {
+				if f, ok := field.(map[string]interface{}); ok {
+					if f["key"] == loginIdField {
+						res["loginIdLabel"] = f["label"]
+						break
+					}
+				}
+			}
+		}
+	}
+
+	return c.JSON(res)
 }
 
 // normalizePhoneForLoginID는 전화번호를 IDP 조회에 적합한 형태(E.164)로 정규화합니다.
diff --git a/backend/internal/handler/user_handler.go b/backend/internal/handler/user_handler.go
index 22ef7582..44fbc1c7 100644
--- a/backend/internal/handler/user_handler.go
+++ b/backend/internal/handler/user_handler.go
@@ -321,11 +321,20 @@ func (h *UserHandler) CreateUser(c *fiber.Ctx) error {
 		"grade":           role,
 	}
 
-	// [Resolve TenantID before Kratos creation]
+	// [Resolve TenantID and LoginID before Kratos creation]
 	var tenantID string
 	if req.CompanyCode != "" && h.TenantService != nil {
 		if tenant, err := h.TenantService.GetTenantBySlug(c.Context(), req.CompanyCode); err == nil && tenant != nil {
 			tenantID = tenant.ID
+
+			// Sync custom field to LoginID if configured
+			if loginIDField, ok := tenant.Config["loginIdField"].(string); ok && loginIDField != "" {
+				if val, exists := req.Metadata[loginIDField]; exists {
+					if loginIDStr, ok := val.(string); ok && loginIDStr != "" {
+						attributes["id"] = loginIDStr
+					}
+				}
+			}
 		}
 	}
 	attributes["role"] = role
@@ -333,6 +342,11 @@ func (h *UserHandler) CreateUser(c *fiber.Ctx) error {
 		attributes["tenant_id"] = tenantID
 	}
 
+	// [Override with explicit LoginID if provided]
+	if req.LoginID != "" {
+		attributes["id"] = req.LoginID
+	}
+
 	// Merge custom metadata into attributes
 	for k, v := range req.Metadata {
 		// Don't overwrite core fields
@@ -343,6 +357,7 @@ func (h *UserHandler) CreateUser(c *fiber.Ctx) error {
 
 	brokerUser := &domain.BrokerUser{
 		Email:       email,
+		LoginID:     extractString(attributes, "id"),
 		Name:        name,
 		PhoneNumber: normalizePhoneNumber(req.Phone),
 		Attributes:  attributes,
@@ -413,6 +428,7 @@ func (h *UserHandler) CreateUser(c *fiber.Ctx) error {
 
 type bulkUserItem struct {
 	Email      string         `json:"email"`
+	LoginID    string         `json:"loginId"`
 	Name       string         `json:"name"`
 	Phone      string         `json:"phone"`
 	Role       string         `json:"role"`
@@ -456,9 +472,10 @@ func (h *UserHandler) BulkCreateUsers(c *fiber.Ctx) error {
 
 	// Pre-fetch tenant data to avoid redundant DB calls
 	type tenantCacheItem struct {
-		ID     string
-		Schema []interface{}
-		Groups []domain.UserGroup
+		ID           string
+		Schema       []interface{}
+		Groups       []domain.UserGroup
+		LoginIDField string
 	}
 	tenantCache := make(map[string]tenantCacheItem)
 
@@ -500,6 +517,9 @@ func (h *UserHandler) BulkCreateUsers(c *fiber.Ctx) error {
 				if s, ok := tenant.Config["userSchema"].([]interface{}); ok {
 					tItem.Schema = s
 				}
+				if lf, ok := tenant.Config["loginIdField"].(string); ok {
+					tItem.LoginIDField = lf
+				}
 				// [Fix] Cache user groups for this tenant to match department
 				if h.UserGroupRepo != nil {
 					if groups, err := h.UserGroupRepo.ListByTenantID(c.Context(), tenant.ID); err == nil {
@@ -537,6 +557,20 @@ func (h *UserHandler) BulkCreateUsers(c *fiber.Ctx) error {
 			"role":            role,
 		}
 
+		// Sync LoginID from configured custom field
+		if tItem.LoginIDField != "" {
+			if val, exists := item.Metadata[tItem.LoginIDField]; exists {
+				if loginIDStr, ok := val.(string); ok && loginIDStr != "" {
+					attributes["id"] = loginIDStr
+				}
+			}
+		}
+
+		// Override with explicit LoginID if provided
+		if item.LoginID != "" {
+			attributes["id"] = item.LoginID
+		}
+
 		// Merge metadata
 		for k, v := range item.Metadata {
 			if _, exists := attributes[k]; !exists {
@@ -546,6 +580,7 @@ func (h *UserHandler) BulkCreateUsers(c *fiber.Ctx) error {
 
 		identityID, err := h.OryProvider.CreateUser(&domain.BrokerUser{
 			Email:       email,
+			LoginID:     extractTraitString(attributes, "id"),
 			Name:        item.Name,
 			PhoneNumber: normalizePhoneNumber(item.Phone),
 			Attributes:  attributes,
@@ -571,6 +606,7 @@ func (h *UserHandler) BulkCreateUsers(c *fiber.Ctx) error {
 			localUser := &domain.User{
 				ID:              identityID,
 				Email:           email,
+				LoginID:         extractTraitString(attributes, "id"),
 				Name:            name,
 				Phone:           normalizePhoneNumber(item.Phone),
 				Role:            role,
@@ -1014,6 +1050,7 @@ func (h *UserHandler) UpdateUser(c *fiber.Ctx) error {
 	}
 
 	var req struct {
+		LoginID     *string        `json:"loginId"`
 		Password    *string        `json:"password"`
 		Name        *string        `json:"name"`
 		Phone       *string        `json:"phone"`
@@ -1113,11 +1150,43 @@ func (h *UserHandler) UpdateUser(c *fiber.Ctx) error {
 		traits["role"] = role
 	}
 
+	// [LoginID Sync based on Tenant Settings]
+	schemaCompCode := extractTraitString(traits, "companyCode")
+	if req.CompanyCode != nil {
+		schemaCompCode = *req.CompanyCode
+	}
+	if schemaCompCode != "" && h.TenantService != nil {
+		if tenant, err := h.TenantService.GetTenantBySlug(c.Context(), schemaCompCode); err == nil && tenant != nil {
+			if loginIDField, ok := tenant.Config["loginIdField"].(string); ok && loginIDField != "" {
+				// Search in Metadata (could be flat or namespaced)
+				if val, exists := req.Metadata[loginIDField]; exists {
+					if loginIDStr, ok := val.(string); ok && loginIDStr != "" {
+						traits["id"] = loginIDStr
+					}
+				} else if namespaced, exists := req.Metadata[tenant.ID]; exists {
+					if subMeta, ok := namespaced.(map[string]any); ok {
+						if val, exists := subMeta[loginIDField]; exists {
+							if loginIDStr, ok := val.(string); ok && loginIDStr != "" {
+								traits["id"] = loginIDStr
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+
+	// [Override with explicit LoginID if provided]
+	if req.LoginID != nil && *req.LoginID != "" {
+		traits["id"] = *req.LoginID
+	}
+
 	// [Namespaced Metadata Sync]
 	coreTraits := map[string]bool{
 		"email": true, "name": true, "phone_number": true,
 		"grade": true, "companyCode": true, "department": true,
 		"affiliationType": true, "role": true, "tenant_id": true,
+		"id": true,
 	}
 
 	// For namespaced metadata, we don't delete everything, we merge.
@@ -1284,6 +1353,7 @@ func (h *UserHandler) mapToLocalUser(identity service.KratosIdentity) *domain.Us
 	user := &domain.User{
 		ID:              identity.ID,
 		Email:           extractTraitString(traits, "email"),
+		LoginID:         extractTraitString(traits, "id"),
 		Name:            extractTraitString(traits, "name"),
 		Phone:           extractTraitString(traits, "phone_number"),
 		Role:            role,
diff --git a/backend/internal/service/ory_service.go b/backend/internal/service/ory_service.go
index bab1e8c0..a4e639cb 100644
--- a/backend/internal/service/ory_service.go
+++ b/backend/internal/service/ory_service.go
@@ -41,7 +41,7 @@ func (o *OryProvider) Name() string {
 func (o *OryProvider) GetMetadata() (*domain.IDPMetadata, error) {
 	return &domain.IDPMetadata{
 		SupportedFields: []string{
-			"id", "email", "name", "phone_number",
+			"id", "login_id", "email", "name", "phone_number",
 			"grade", "department", "affiliationType", "companyCode",
 		},
 	}, nil
@@ -64,6 +64,17 @@ func (o *OryProvider) CreateUser(user *domain.BrokerUser, password string) (stri
 	if existingID != "" {
 		return "", fmt.Errorf("ory provider: identity already exists for email=%s", user.Email)
 	}
+
+	if user.LoginID != "" {
+		existingLoginID, err := o.findIdentityID(user.LoginID)
+		if err != nil {
+			return "", fmt.Errorf("ory provider: search identity failed: %w", err)
+		}
+		if existingLoginID != "" {
+			return "", fmt.Errorf("ory provider: identity already exists for login_id=%s", user.LoginID)
+		}
+	}
+
 	if user.PhoneNumber != "" {
 		existingPhoneID, err := o.findIdentityID(user.PhoneNumber)
 		if err != nil {
@@ -78,6 +89,9 @@ func (o *OryProvider) CreateUser(user *domain.BrokerUser, password string) (stri
 		"email": user.Email,
 		"name":  user.Name,
 	}
+	if user.LoginID != "" {
+		traits["id"] = user.LoginID
+	}
 	if user.PhoneNumber != "" {
 		traits["phone_number"] = user.PhoneNumber
 	}
diff --git a/docker/ory/kratos/identity.schema.json b/docker/ory/kratos/identity.schema.json
index c872f2f7..3582a5f4 100644
--- a/docker/ory/kratos/identity.schema.json
+++ b/docker/ory/kratos/identity.schema.json
@@ -7,6 +7,17 @@
     "traits": {
       "type": "object",
       "properties": {
+        "id": {
+          "type": "string",
+          "title": "ID",
+          "ory.sh/kratos": {
+            "credentials": {
+              "password": {
+                "identifier": true
+              }
+            }
+          }
+        },
         "email": {
           "type": "string",
           "format": "email",
diff --git a/docs/employee_id_login_db_design.md b/docs/employee_id_login_db_design.md
new file mode 100644
index 00000000..b5eac0f3
--- /dev/null
+++ b/docs/employee_id_login_db_design.md
@@ -0,0 +1,53 @@
+# 커스텀 필드 기반 로그인 ID 연동 - DB 설계 문서
+
+## 1. 개요
+본 문서는 사용자(User) 정보에 범용 로그인 ID(`login_id`)를 추가하고, 이를 테넌트별 설정에 따라 커스텀 필드와 동기화하기 위한 **데이터베이스(DB) 관점의 설계 변경 사항**을 명세합니다.
+
+## 2. DB 스키마 변경 사항
+
+### 2.1. 대상 테이블: `users`
+
+현재 백엔드(PostgreSQL)의 `users` 테이블에 `login_id` 컬럼을 추가합니다.
+
+| 컬럼명 | 타입 | 제약 조건 | 설명 |
+| :--- | :--- | :--- | :--- |
+| `login_id` | `VARCHAR(255)` | `NULL` 허용 | 범용 로그인 식별자 (사번, 학번 등) |
+
+#### 인덱스(Index) 설정
+단순 `unique`가 아닌, **테넌트 내 고유성**을 보장하기 위해 `tenant_id`와 조합된 복합 유니크 인덱스를 생성합니다.
+*   **인덱스명**: `idx_tenant_login_id`
+*   **구성 컬럼**: `(tenant_id, login_id)`
+*   **효과**: 
+    *   서로 다른 테넌트 간에는 동일한 `login_id`가 존재할 수 있습니다.
+    *   동일 테넌트 내에서는 중복된 `login_id`를 가질 수 없습니다.
+
+### 2.2. 대상 테이블: `tenants`
+
+`tenants` 테이블의 `config` (JSONB) 컬럼에 매핑 설정을 추가합니다.
+
+*   **설정 키**: `loginIdField`
+*   **설명**: 사용자의 `metadata` (커스텀 필드) 중 어떤 필드의 값을 `login_id`로 동기화할지 결정하는 필드 키 이름입니다.
+*   **예시**: `"loginIdField": "emp_no"`
+
+## 3. 데이터 흐름 및 동기화
+
+### 3.1. 사용자 생성/수정 (Sync Flow)
+1.  사용자 생성/수정 시 전달된 `metadata`와 테넌트의 `config.loginIdField`를 확인합니다.
+2.  `metadata` 내에 해당 키의 값이 존재하면, 그 값을 `users.login_id` 컬럼에 저장합니다.
+3.  동시에 Ory Kratos의 `traits.id` 필드에도 해당 값을 업데이트하여 Kratos를 통한 로그인을 가능하게 합니다.
+
+### 3.2. 대량 업로드 (Bulk Import)
+1.  CSV/Excel 파일의 컬럼 중 테넌트에서 지정한 커스텀 필드 컬럼(예: 사번)을 파싱합니다.
+2.  위의 동기화 로직과 동일하게 `login_id` 컬럼과 Kratos Traits를 업데이트합니다.
+
+## 4. GORM 모델 반영 (Go)
+
+```go
+type User struct {
+    ID       string  `gorm:"primaryKey;type:uuid"`
+    Email    string  `gorm:"uniqueIndex;not null"`
+    LoginID  string  `gorm:"column:login_id;uniqueIndex:idx_tenant_login_id"`
+    TenantID *string `gorm:"column:tenant_id;type:uuid;uniqueIndex:idx_tenant_login_id"`
+    // ... 기타 필드
+}
+```
diff --git a/docs/employee_id_login_design.md b/docs/employee_id_login_design.md
new file mode 100644
index 00000000..8af6a7b1
--- /dev/null
+++ b/docs/employee_id_login_design.md
@@ -0,0 +1,47 @@
+# 커스텀 필드 기반 로그인 ID 연동 설계 문서 (구 사번 로그인)
+
+## 1. 개요
+기존에 고정된 사번(`employee_id`) 필드를 사용하려던 설계를 변경하여, 테넌트별로 지정한 **커스텀 필드**를 실제 로그인 식별자로 사용할 수 있도록 하는 범용적인 로그인 ID 체계를 구축합니다.
+
+## 2. 시스템별 변경 사항
+
+### 2.1. Ory Kratos (인증 서버)
+*   **Identity Schema**: `traits` 내에 `id` 필드를 추가합니다.
+*   **Identifier 설정**: `traits.id`를 `credentials.password.identifier`로 설정하여 로그인 시 식별자로 사용할 수 있게 합니다.
+*   **특징**: 이 필드는 '사번', '학번', 'ID' 등 테넌트의 성격에 따라 다양한 용도로 활용되는 범용 식별자 역할을 합니다.
+
+### 2.2. Backend (baron-sso-backend)
+
+#### 데이터 모델 (`domain.User`)
+*   `login_id` (string) 컬럼 추가.
+*   `idx_tenant_login_id` 복합 유니크 인덱스 생성: `(tenant_id, login_id)`.
+
+#### 테넌트 설정 (`domain.Tenant`)
+*   `Config` 내에 `loginIdField` 설정을 추가합니다.
+*   이 설정은 해당 테넌트의 `userSchema` 중 어떤 필드(key)가 로그인 ID로 사용될지를 저장합니다.
+
+#### 동기화 로직 (`UserHandler`)
+*   **사용자 생성/수정 시**:
+    1.  테넌트의 `loginIdField` 설정을 조회합니다.
+    2.  설정된 필드가 있다면 사용자의 `Metadata`에서 해당 값을 추출합니다.
+    3.  추출된 값을 Kratos의 `traits.id`와 로컬 DB의 `login_id` 컬럼에 동기화합니다.
+*   **대량 등록 (Bulk Import)**: CSV/JSON 업로드 시에도 동일한 동기화 로직이 적용됩니다.
+
+### 2.3. Frontend (adminfront)
+
+#### 테넌트 스키마 관리 (`TenantSchemaPage`)
+*   커스텀 필드 정의 시 "로그인 ID로 사용" 체크박스를 추가합니다.
+*   이 체크박스를 선택하면 해당 필드의 `key`가 테넌트 `Config.loginIdField`에 저장됩니다.
+
+#### 사용자 관리 (`UserCreatePage`, `UserDetailPage`)
+*   기본 정보 영역에 "로그인 ID" 필드를 노출하여 직접 관리할 수 있게 합니다.
+
+### 2.4. Frontend (userfront)
+
+#### 로그인 페이지 (`LoginScreen`)
+*   URL의 `companyCode` 또는 도메인을 통해 테넌트를 식별합니다.
+*   해당 테넌트에 `loginIdField`가 설정되어 있다면, 로그인 입력란의 라벨을 해당 커스텀 필드의 라벨(예: "사번")로 동적으로 변경합니다.
+
+## 3. 기대 효과
+*   테넌트별로 상이한 로그인 식별자 요구사항(사번, 학생번호, 커스텀 ID 등)을 코드 수정 없이 유연하게 수용할 수 있습니다.
+*   이메일, 전화번호 외의 추가적인 로그인 수단을 제공하여 사용자 편의성을 높입니다.
diff --git a/locales/en.toml b/locales/en.toml
index e1002e87..a4dfd61c 100644
--- a/locales/en.toml
+++ b/locales/en.toml
@@ -1031,6 +1031,7 @@ key_placeholder = "e.g. employee_id"
 label = "Display Label"
 label_placeholder = "Label Placeholder"
 required = "Required"
+is_login_id = "Use as Login ID"
 type = "Type"
 type_boolean = "Boolean"
 type_date = "Date"
@@ -1104,6 +1105,8 @@ department = "Department"
 department_placeholder = "Department Placeholder"
 email = "Email"
 email_placeholder = "user@example.com"
+login_id = "Login ID (Optional)"
+login_id_placeholder = "Employee ID or ID"
 job_title = "Job Title"
 job_title_placeholder = "e.g. Frontend Developer"
 name = "Name"
@@ -1136,6 +1139,8 @@ multi_title = "Per-tenant Profile Management"
 [ui.admin.users.detail.form]
 department = "Department"
 department_placeholder = "Department Placeholder"
+login_id = "Login ID"
+login_id_placeholder = "Employee ID or Username"
 name = "Name"
 name_placeholder = "Name Placeholder"
 phone = "Phone number"
@@ -1181,6 +1186,7 @@ title = "User Registry"
 [ui.admin.users.list.table]
 actions = "ACTIONS"
 created = "CREATED"
+login_id = "LOGIN ID"
 name_email = "NAME / EMAIL"
 role = "ROLE"
 status = "STATUS"
diff --git a/locales/ko.toml b/locales/ko.toml
index 3ee28279..f94ab36a 100644
--- a/locales/ko.toml
+++ b/locales/ko.toml
@@ -1531,6 +1531,7 @@ key_placeholder = "e.g. employee_id"
 label = "표시 레이블"
 label_placeholder = "예: 사번"
 required = "필수 여부"
+is_login_id = "로그인 ID로 사용"
 type = "타입"
 type_boolean = "Boolean"
 type_date = "Date"
@@ -1563,6 +1564,8 @@ department = "부서"
 department_placeholder = "개발팀"
 email = "이메일"
 email_placeholder = "user@example.com"
+login_id = "로그인 ID (선택)"
+login_id_placeholder = "사번 또는 아이디"
 job_title = "직무"
 job_title_placeholder = "프론트엔드 개발"
 name = "이름"
@@ -1589,6 +1592,8 @@ multi_title = "테넌트별 프로필 관리"
 [ui.admin.users.detail.form]
 department = "부서"
 department_placeholder = "개발팀"
+login_id = "로그인 ID"
+login_id_placeholder = "사번 또는 아이디"
 name = "이름"
 name_placeholder = "홍길동"
 phone = "전화번호"
@@ -1625,6 +1630,7 @@ title = "사용자 레지스트리"
 [ui.admin.users.list.table]
 actions = "ACTIONS"
 created = "CREATED"
+login_id = "LOGIN ID"
 name_email = "NAME / EMAIL"
 role = "ROLE"
 status = "STATUS"
diff --git a/userfront/lib/core/services/auth_proxy_service.dart b/userfront/lib/core/services/auth_proxy_service.dart
index 3dd1dc14..ec2c1a24 100644
--- a/userfront/lib/core/services/auth_proxy_service.dart
+++ b/userfront/lib/core/services/auth_proxy_service.dart
@@ -110,6 +110,19 @@ class AuthProxyService {
     }
   }
 
+  static Future<Map<String, dynamic>> getTenantInfo() async {
+    final url = Uri.parse('$_baseUrl/api/v1/auth/tenant-info');
+    final response = await http.get(url);
+    if (response.statusCode == 200) {
+      return jsonDecode(response.body);
+    } else {
+      throw _error(
+        'err.userfront.auth_proxy.tenant_info_fetch',
+        '테넌트 정보를 불러오지 못했습니다.',
+      );
+    }
+  }
+
   static Future<Map<String, dynamic>> initEnchantedLink(
     String loginId, {
     String? method,
diff --git a/userfront/lib/features/auth/presentation/login_screen.dart b/userfront/lib/features/auth/presentation/login_screen.dart
index dad569bf..86f08faf 100644
--- a/userfront/lib/features/auth/presentation/login_screen.dart
+++ b/userfront/lib/features/auth/presentation/login_screen.dart
@@ -48,6 +48,7 @@ class _LoginScreenState extends ConsumerState<LoginScreen>
   String? _redirectUrl;
   String? _loginChallenge;
   bool _isPasswordCapsLockOn = false;
+  String? _loginIdLabel;
 
   // QR Login Variables
   String? _qrImageBase64;
@@ -150,6 +151,19 @@ class _LoginScreenState extends ConsumerState<LoginScreen>
       if (!_verificationOnly) {
         await _attemptOidcAutoAccept();
         if (!mounted) return;
+
+        // Fetch Tenant Info to check for custom login ID label
+        try {
+          final info = await AuthProxyService.getTenantInfo();
+          if (info['loginIdLabel'] != null) {
+            setState(() {
+              _loginIdLabel = info['loginIdLabel'];
+            });
+          }
+        } catch (e) {
+          debugPrint("[Auth] Failed to fetch tenant info: $e");
+        }
+
         // login_challenge 흐름에서는 auto-accept에서 이미 쿠키 세션까지 확인하므로
         // 동일 프레임에서 중복 체크를 피합니다.
         if (!_hasLoginChallenge) {
@@ -1456,7 +1470,7 @@ class _LoginScreenState extends ConsumerState<LoginScreen>
                                     ),
                                     controller: _passwordLoginIdController,
                                     decoration: InputDecoration(
-                                      labelText: tr(
+                                      labelText: _loginIdLabel ?? tr(
                                         'ui.userfront.login.field.login_id',
                                       ),
                                       border: const OutlineInputBorder(),