diff --git a/devfront/src/features/clients/ClientGeneralPage.tsx b/devfront/src/features/clients/ClientGeneralPage.tsx
index 172e9366..7885825f 100644
--- a/devfront/src/features/clients/ClientGeneralPage.tsx
+++ b/devfront/src/features/clients/ClientGeneralPage.tsx
@@ -5,7 +5,6 @@ import {
   Info,
   Plus,
   Save,
-  Search,
   Shield,
   ShieldHalf,
   Sparkles,
@@ -36,7 +35,6 @@ import type {
   ClientStatus,
   ClientType,
   ClientUpsertRequest,
-  MyTenantSummary,
   TenantSummary,
 } from "../../lib/devApi";
 import {
@@ -45,7 +43,7 @@ import {
   deleteClient,
   fetchClient,
   fetchClientRelations,
-  fetchMyTenants,
+  fetchTenants,
   refreshHeadlessJwksCache,
   revokeHeadlessJwksCache,
   updateClient,
@@ -58,6 +56,7 @@ import { fetchMe, type UserProfile } from "../auth/authApi";
 import { useDeveloperAccessGate } from "../developer-access/developerAccessGate";
 import { ClientDetailTabs } from "./ClientDetailTabs";
 import { AllowedTenantBadge } from "./components/AllowedTenantBadge";
+import { TenantAccessPicker } from "./components/TenantAccessPicker";
 import {
   claimDateTimeValueToInputString,
   dateTimeInputToUnixSeconds,
@@ -597,8 +596,8 @@ function ClientGeneralPage() {
     retry: false,
   });
   const { data: tenantData } = useQuery({
-    queryKey: ["my-tenants"],
-    queryFn: fetchMyTenants,
+    queryKey: ["tenants", "all"],
+    queryFn: () => fetchTenants(),
   });
 
   const [name, setName] = useState("");
@@ -622,8 +621,6 @@ function ClientGeneralPage() {
   ] = useState(false);
   const [tenantAccessRestricted, setTenantAccessRestricted] = useState(false);
   const [allowedTenantIds, setAllowedTenantIds] = useState<string[]>([]);
-  const [tenantSearch, setTenantSearch] = useState("");
-  const [isTenantSearchOpen, setIsTenantSearchOpen] = useState(false);
   const [autoLoginSupported, setAutoLoginSupported] = useState(false);
   const [autoLoginUrl, setAutoLoginUrl] = useState("");
 
@@ -990,10 +987,6 @@ function ClientGeneralPage() {
 
   const handleTenantAccessToggle = (enabled: boolean) => {
     setTenantAccessRestricted(enabled);
-    setIsTenantSearchOpen(enabled);
-    if (!enabled) {
-      setTenantSearch("");
-    }
     setScopes((current) => normalizeScopesForTenantAccess(current, enabled));
   };
 
@@ -1009,8 +1002,6 @@ function ClientGeneralPage() {
     setAllowedTenantIds((current) =>
       current.includes(tenantId) ? current : [...current, tenantId],
     );
-    setTenantSearch("");
-    setIsTenantSearchOpen(true);
   };
 
   const addScope = () => {
@@ -1270,25 +1261,10 @@ function ClientGeneralPage() {
     normalizedIdTokenClaimItems,
   );
   const idTokenClaimPreviewJson = JSON.stringify(idTokenClaimPreview, null, 2);
-  const normalizedTenantSearch = tenantSearch.trim().toLowerCase();
-  const tenantOptions: Array<TenantSummary | MyTenantSummary> =
-    tenantData ?? [];
-  const filteredTenants = tenantOptions.filter((tenant) => {
-    if (!normalizedTenantSearch) {
-      return true;
-    }
-    const searchable =
-      `${tenant.name} ${tenant.slug} ${tenant.description ?? ""} ${tenant.type ?? ""}`.toLowerCase();
-    return searchable.includes(normalizedTenantSearch);
-  });
-  const tenantSuggestions = filteredTenants
-    .filter((tenant) => !allowedTenantIds.includes(tenant.id))
-    .slice(0, 8);
+  const tenantOptions: TenantSummary[] = tenantData?.items ?? [];
   const selectedAllowedTenants = allowedTenantIds
     .map((tenantId) => tenantOptions.find((item) => item.id === tenantId))
-    .filter(
-      (tenant): tenant is TenantSummary | MyTenantSummary => tenant != null,
-    );
+    .filter((tenant): tenant is TenantSummary => tenant != null);
 
   const refreshHeadlessJwksCacheMutation = useMutation({
     mutationFn: async () => {
@@ -2368,92 +2344,19 @@ function ClientGeneralPage() {
 
           <div className="grid gap-4 lg:grid-cols-[1.2fr_0.8fr]">
             <div className="space-y-3">
-              <Label htmlFor="tenant-search" className="text-sm font-semibold">
+              <Label className="text-sm font-semibold">
                 {t(
-                  "ui.dev.clients.general.tenant_access.search_placeholder",
-                  "테넌트 이름 또는 슬러그로 검색",
+                  "ui.dev.clients.general.tenant_access.picker_label",
+                  "허용 테넌트 추가",
                 )}
               </Label>
-              <div className="relative">
-                <Search className="pointer-events-none absolute left-3 top-1/2 h-4 w-4 -translate-y-1/2 text-muted-foreground" />
-                <Input
-                  id="tenant-search"
-                  value={tenantSearch}
-                  onFocus={() => {
-                    if (tenantAccessRestricted) {
-                      setIsTenantSearchOpen(true);
-                    }
-                  }}
-                  onBlur={() => {
-                    window.setTimeout(() => setIsTenantSearchOpen(false), 120);
-                  }}
-                  onChange={(e) => {
-                    setTenantSearch(e.target.value);
-                    if (tenantAccessRestricted) {
-                      setIsTenantSearchOpen(true);
-                    }
-                  }}
-                  placeholder={t(
-                    "ui.dev.clients.general.tenant_access.search_placeholder",
-                    "테넌트 이름 또는 슬러그로 검색",
-                  )}
-                  className="pl-10"
-                  disabled={
-                    isGeneralSettingsReadOnly || !tenantAccessRestricted
-                  }
-                />
-                {tenantAccessRestricted && isTenantSearchOpen && (
-                  <div className="absolute z-20 mt-2 max-h-72 w-full overflow-y-auto rounded-xl border border-border bg-background shadow-lg">
-                    {tenantSuggestions.length > 0 ? (
-                      tenantSuggestions.map((tenant) => (
-                        <button
-                          key={tenant.id}
-                          type="button"
-                          className="flex w-full items-start justify-between gap-3 border-b border-border/40 px-4 py-3 text-left transition hover:bg-muted/40 last:border-b-0"
-                          onMouseDown={(event) => {
-                            event.preventDefault();
-                            handleSelectAllowedTenant(tenant.id);
-                          }}
-                          disabled={isGeneralSettingsReadOnly}
-                        >
-                          <div className="min-w-0 space-y-1">
-                            <div className="flex items-center gap-2">
-                              <span className="truncate font-medium">
-                                {tenant.name}
-                              </span>
-                              <Badge variant="outline" className="text-[11px]">
-                                {tenant.slug}
-                              </Badge>
-                            </div>
-                            <p className="truncate text-xs text-muted-foreground">
-                              {tenant.description || tenant.type}
-                            </p>
-                          </div>
-                          <Plus className="mt-0.5 h-4 w-4 shrink-0 text-muted-foreground" />
-                        </button>
-                      ))
-                    ) : (
-                      <div className="px-4 py-8 text-center text-sm text-muted-foreground">
-                        {t(
-                          "ui.dev.clients.general.tenant_access.empty",
-                          "검색 결과가 없습니다.",
-                        )}
-                      </div>
-                    )}
-                  </div>
-                )}
-              </div>
-              <div className="rounded-xl border border-dashed border-border bg-muted/20 px-4 py-3 text-sm text-muted-foreground">
-                {tenantAccessRestricted
-                  ? t(
-                      "ui.dev.clients.general.tenant_access.autocomplete_hint",
-                      "테넌트 이름을 입력하면 자동 완성 후보가 나타납니다. 클릭하면 허용 목록에 추가됩니다.",
-                    )
-                  : t(
-                      "ui.dev.clients.general.tenant_access.disabled",
-                      "제한 없음",
-                    )}
-              </div>
+              <TenantAccessPicker
+                disabled={isGeneralSettingsReadOnly || !tenantAccessRestricted}
+                selectedCount={allowedTenantIds.length}
+                onSelectTenant={(selection) =>
+                  handleSelectAllowedTenant(selection.id)
+                }
+              />
             </div>
 
             <div className="space-y-3">
diff --git a/devfront/src/features/clients/components/TenantAccessPicker.tsx b/devfront/src/features/clients/components/TenantAccessPicker.tsx
new file mode 100644
index 00000000..f787eed5
--- /dev/null
+++ b/devfront/src/features/clients/components/TenantAccessPicker.tsx
@@ -0,0 +1,146 @@
+import { Building2 } from "lucide-react";
+import { useEffect, useMemo, useState } from "react";
+import { createPortal } from "react-dom";
+import { Button } from "../../../components/ui/button";
+import { t } from "../../../lib/i18n";
+import {
+  buildAuthenticatedOrgChartTenantPickerUrl,
+  type OrgChartTenantSelection,
+  parseOrgChartTenantSelection,
+} from "../orgChartPicker";
+
+type TenantAccessPickerProps = {
+  disabled?: boolean;
+  selectedCount: number;
+  onSelectTenant: (selection: OrgChartTenantSelection) => void;
+};
+
+function resolveOrgFrontBaseUrl() {
+  return (
+    import.meta.env.VITE_ORGFRONT_PUBLIC_URL ||
+    import.meta.env.ORGFRONT_URL ||
+    "http://localhost:5175"
+  );
+}
+
+export function TenantAccessPicker({
+  disabled = false,
+  selectedCount,
+  onSelectTenant,
+}: TenantAccessPickerProps) {
+  const [pickerOpen, setPickerOpen] = useState(false);
+  const pickerUrl = useMemo(
+    () => buildAuthenticatedOrgChartTenantPickerUrl(resolveOrgFrontBaseUrl()),
+    [],
+  );
+
+  useEffect(() => {
+    if (!pickerOpen) return;
+
+    const onMessage = (event: MessageEvent) => {
+      const selection = parseOrgChartTenantSelection(event.data);
+      if (!selection) return;
+      onSelectTenant(selection);
+      setPickerOpen(false);
+    };
+
+    window.addEventListener("message", onMessage);
+    return () => window.removeEventListener("message", onMessage);
+  }, [onSelectTenant, pickerOpen]);
+
+  const pickerDialog =
+    pickerOpen && typeof document !== "undefined"
+      ? createPortal(
+          <div
+            className="fixed inset-0 z-[1000] flex items-start justify-center overflow-y-auto bg-black/50 p-4 md:items-center"
+            role="dialog"
+            aria-modal="true"
+            aria-label={t(
+              "ui.dev.clients.general.tenant_access.picker_title",
+              "테넌트 선택",
+            )}
+          >
+            <div className="flex h-[92vh] w-[min(96vw,1200px)] flex-col overflow-hidden rounded-2xl border border-border bg-background p-4 shadow-2xl">
+              <div className="flex items-start justify-between gap-3">
+                <div className="space-y-1">
+                  <h2 className="text-lg font-semibold">
+                    {t(
+                      "ui.dev.clients.general.tenant_access.picker_title",
+                      "테넌트 선택",
+                    )}
+                  </h2>
+                  <p className="text-sm text-muted-foreground">
+                    {t(
+                      "msg.dev.clients.general.tenant_access.picker_description",
+                      "orgfront 조직도에서 허용할 테넌트를 선택하면 목록에 추가됩니다.",
+                    )}
+                  </p>
+                </div>
+                <Button
+                  type="button"
+                  variant="ghost"
+                  size="sm"
+                  className="shrink-0"
+                  onClick={() => setPickerOpen(false)}
+                >
+                  {t("ui.common.close", "닫기")}
+                </Button>
+              </div>
+              <div className="mt-4 min-h-0 flex-1 overflow-hidden rounded-md border">
+                <iframe
+                  title={t(
+                    "ui.dev.clients.general.tenant_access.picker_title",
+                    "테넌트 선택",
+                  )}
+                  src={pickerUrl}
+                  className="h-full w-full"
+                />
+              </div>
+              <div className="mt-4 flex shrink-0 justify-end">
+                <Button
+                  type="button"
+                  variant="outline"
+                  onClick={() => setPickerOpen(false)}
+                >
+                  {t("ui.common.close", "닫기")}
+                </Button>
+              </div>
+            </div>
+          </div>,
+          document.body,
+        )
+      : null;
+
+  return (
+    <div className="space-y-3">
+      <Button
+        type="button"
+        variant="outline"
+        className="h-10 gap-2"
+        disabled={disabled}
+        onClick={() => setPickerOpen(true)}
+      >
+        <Building2 className="h-4 w-4" />
+        {t(
+          "ui.dev.clients.general.tenant_access.open_picker",
+          "테넌트 선택기 열기",
+        )}
+      </Button>
+
+      {pickerDialog}
+
+      <div className="rounded-xl border border-dashed border-border bg-muted/20 px-4 py-3 text-sm text-muted-foreground">
+        {selectedCount > 0
+          ? t(
+              "msg.dev.clients.general.tenant_access.picker_hint_with_count",
+              "선택기를 열어 허용 테넌트를 추가하세요. 현재 {{count}}개가 선택되어 있습니다.",
+              { count: selectedCount },
+            )
+          : t(
+              "msg.dev.clients.general.tenant_access.picker_hint",
+              "선택기를 열어 허용 테넌트를 추가하세요.",
+            )}
+      </div>
+    </div>
+  );
+}
diff --git a/devfront/src/features/clients/orgChartPicker.ts b/devfront/src/features/clients/orgChartPicker.ts
new file mode 100644
index 00000000..1503db59
--- /dev/null
+++ b/devfront/src/features/clients/orgChartPicker.ts
@@ -0,0 +1,91 @@
+export type OrgChartTenantSelection = {
+  id: string;
+  name: string;
+};
+
+type OrgChartPickerMessage = {
+  type?: unknown;
+  payload?: {
+    selections?: Array<{
+      type?: unknown;
+      id?: unknown;
+      name?: unknown;
+    }>;
+  };
+};
+
+type OrgChartTenantPickerOptions = {
+  includeInternal?: boolean;
+  tenantId?: string;
+};
+
+function buildAuthenticatedOrgChartUrl(
+  baseUrl?: string,
+  options: { includeInternal?: boolean; returnTo?: string } = {},
+) {
+  const normalizedBase = (baseUrl ?? "").replace(/\/+$/, "");
+  let returnTo = options.returnTo?.trim() || "/chart";
+  if (options.includeInternal && returnTo.startsWith("/chart")) {
+    const [path, query = ""] = returnTo.split("?", 2);
+    const params = new URLSearchParams(query);
+    params.set("includeInternal", "true");
+    returnTo = `${path}?${params.toString()}`;
+  }
+  const params = new URLSearchParams({
+    auto: "1",
+    returnTo,
+  });
+
+  return `${normalizedBase}/login?${params.toString()}`;
+}
+
+export function buildAuthenticatedOrgChartTenantPickerUrl(
+  baseUrl?: string,
+  options: OrgChartTenantPickerOptions = {},
+) {
+  const normalizedBase = (baseUrl ?? "").trim() || "http://localhost:5175";
+  const params = new URLSearchParams({
+    mode: "single",
+    select: "tenant",
+    width: "400",
+    height: "600",
+  });
+
+  const tenantId = options.tenantId?.trim();
+  if (tenantId) {
+    params.set("tenantId", tenantId);
+  }
+  if (options.includeInternal) {
+    params.set("includeInternal", "true");
+  }
+
+  const pickerUrl = `/embed/picker?${params.toString()}`;
+  return buildAuthenticatedOrgChartUrl(normalizedBase, {
+    includeInternal: true,
+    returnTo: pickerUrl,
+  });
+}
+
+export function parseOrgChartTenantSelection(
+  message: unknown,
+): OrgChartTenantSelection | null {
+  const data = message as OrgChartPickerMessage;
+  if (data?.type !== "orgfront:picker:confirm") {
+    return null;
+  }
+
+  const selection = data.payload?.selections?.[0];
+  if (
+    selection?.type !== "tenant" ||
+    typeof selection.id !== "string" ||
+    typeof selection.name !== "string" ||
+    selection.id.trim() === ""
+  ) {
+    return null;
+  }
+
+  return {
+    id: selection.id,
+    name: selection.name,
+  };
+}