diff --git a/adminfront/src/components/layout/AppLayout.tsx b/adminfront/src/components/layout/AppLayout.tsx
index 9f42e384..3cf40297 100644
--- a/adminfront/src/components/layout/AppLayout.tsx
+++ b/adminfront/src/components/layout/AppLayout.tsx
@@ -80,9 +80,19 @@ function AppLayout() {
     };
   }, []);
 
-  const { data: profile } = useQuery({
+  const { data: profile, isLoading: isProfileLoading, error: profileError } = useQuery({
     queryKey: ["me"],
-    queryFn: fetchMe,
+    queryFn: async () => {
+      console.debug("[AppLayout] Fetching profile...");
+      try {
+        const data = await fetchMe();
+        console.debug("[AppLayout] Profile fetched successfully:", data.email);
+        return data;
+      } catch (err) {
+        console.error("[AppLayout] Failed to fetch profile:", err);
+        throw err;
+      }
+    },
     enabled:
       (auth.isAuthenticated && !auth.isLoading) ||
       import.meta.env.MODE === "development" ||
@@ -170,7 +180,15 @@ function AppLayout() {
     const isTest =
       (window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean })
         ._IS_TEST_MODE === true;
+    
+    console.debug("[AppLayout] Auth state check:", {
+      isLoading: auth.isLoading,
+      isAuthenticated: auth.isAuthenticated,
+      isTest
+    });
+
     if (!auth.isLoading && !auth.isAuthenticated && !isTest) {
+      console.warn("[AppLayout] Not authenticated, redirecting to /login");
       navigate("/login");
     }
   }, [auth.isLoading, auth.isAuthenticated, navigate]);
diff --git a/adminfront/src/features/auth/AuthCallbackPage.tsx b/adminfront/src/features/auth/AuthCallbackPage.tsx
index ed1e0630..b6c711d7 100644
--- a/adminfront/src/features/auth/AuthCallbackPage.tsx
+++ b/adminfront/src/features/auth/AuthCallbackPage.tsx
@@ -8,6 +8,11 @@ function AuthCallbackPage() {
   const navigate = useNavigate();
 
   useEffect(() => {
+    console.debug("[AuthCallbackPage] State:", {
+      isAuthenticated: auth.isAuthenticated,
+      isLoading: auth.isLoading,
+      error: auth.error
+    });
     if (auth.isAuthenticated) {
       // Save token to localStorage for existing API clients that might still use it
       const user = auth.user;
@@ -21,12 +26,13 @@ function AuthCallbackPage() {
         typeof auth.user.state.returnTo === "string"
           ? auth.user.state.returnTo
           : "/";
+      console.info("[AuthCallbackPage] Auth successful, navigating to", returnTo);
       navigate(returnTo, { replace: true });
     } else if (auth.error) {
-      console.error("Auth Error:", auth.error);
+      console.error("[AuthCallbackPage] Auth Error:", auth.error);
       navigate("/login", { replace: true });
     }
-  }, [auth.isAuthenticated, auth.error, navigate, auth.user]);
+  }, [auth.isAuthenticated, auth.error, navigate, auth.user, auth.isLoading]);
 
   return (
     <div className="flex min-h-screen items-center justify-center bg-background">
diff --git a/adminfront/src/features/auth/LoginPage.tsx b/adminfront/src/features/auth/LoginPage.tsx
index 3c46ac63..42f560ad 100644
--- a/adminfront/src/features/auth/LoginPage.tsx
+++ b/adminfront/src/features/auth/LoginPage.tsx
@@ -20,10 +20,16 @@ function LoginPage() {
   const shouldAutoLogin = searchParams.get("auto") === "1";
 
   useEffect(() => {
+    console.debug("[LoginPage] Auth state check:", {
+      isAuthenticated: auth.isAuthenticated,
+      isLoading: auth.isLoading,
+      returnTo
+    });
     if (auth.isAuthenticated) {
+      console.info("[LoginPage] User is authenticated, redirecting to", returnTo);
       navigate(returnTo, { replace: true });
     }
-  }, [auth.isAuthenticated, navigate, returnTo]);
+  }, [auth.isAuthenticated, navigate, returnTo, auth.isLoading]);
 
   useEffect(() => {
     if (!shouldAutoLogin) {
@@ -72,8 +78,8 @@ function LoginPage() {
             </div>
             <p className="opacity-90">{auth.error.message}</p>
             <Button
-              variant="link"
-              className="p-0 h-auto text-destructive underline mt-2"
+              variant="ghost"
+              className="p-0 h-auto text-destructive underline mt-2 hover:bg-transparent"
               onClick={() => {
                 window.location.href =
                   window.location.origin + window.location.pathname;
diff --git a/adminfront/src/lib/apiClient.ts b/adminfront/src/lib/apiClient.ts
index aae7b63b..1d2ccef3 100644
--- a/adminfront/src/lib/apiClient.ts
+++ b/adminfront/src/lib/apiClient.ts
@@ -1,4 +1,5 @@
 import axios from "axios";
+import { userManager } from "./auth";
 
 const apiClient = axios.create({
   baseURL: (window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean })
@@ -7,14 +8,16 @@ const apiClient = axios.create({
     : (import.meta.env.VITE_ADMIN_API_BASE ?? "/api"),
 });
 
-apiClient.interceptors.request.use((config) => {
-  // TODO: IdP 중립 Auth 레이어 연동 시 세션 토큰을 주입한다.
-  const sessionToken = window.localStorage.getItem("admin_session");
+apiClient.interceptors.request.use(async (config) => {
+  // IdP 중립 Auth 레이어 연동: oidc-client의 userManager에서 최신 토큰을 가져옵니다.
+  const user = await userManager.getUser();
+  const sessionToken = user?.access_token || window.localStorage.getItem("admin_session");
+
   if (sessionToken) {
     config.headers.Authorization = `Bearer ${sessionToken}`;
   }
 
-  // TODO: 테넌트 선택 값을 보관하고 헤더로 전달한다.
+  // 테넌트 선택 값을 보관하고 헤더로 전달한다.
   const tenantId = window.localStorage.getItem("admin_tenant");
   if (tenantId) {
     config.headers["X-Tenant-ID"] = tenantId;
@@ -33,10 +36,24 @@ apiClient.interceptors.request.use((config) => {
 
 apiClient.interceptors.response.use(
   (response) => response,
-  (error) => {
+  async (error) => {
     if (error.response?.status === 401) {
+      console.warn("[apiClient] 401 Unauthorized detected. Clearing session state.");
+      
+      // 로컬 스토리지의 세션 키 제거
       window.localStorage.removeItem("admin_session");
-      window.location.href = "/login";
+      
+      // oidc-client의 유저 상태도 제거하여 isAuthenticated를 false로 만듭니다.
+      // 이를 통해 LoginPage에서의 무한 리다이렉션 루프를 방지합니다.
+      await userManager.removeUser();
+
+      const isAuthPath = window.location.pathname.startsWith("/auth/callback");
+      const isLoginPath = window.location.pathname === "/login";
+
+      if (!isAuthPath && !isLoginPath) {
+        console.info("[apiClient] Redirecting to /login from", window.location.pathname);
+        window.location.href = "/login";
+      }
     }
     return Promise.reject(error);
   },
diff --git a/adminfront/src/lib/sessionSliding.ts b/adminfront/src/lib/sessionSliding.ts
index be152778..2ad916b4 100644
--- a/adminfront/src/lib/sessionSliding.ts
+++ b/adminfront/src/lib/sessionSliding.ts
@@ -29,18 +29,28 @@ export function shouldAttemptSlidingSessionRenew({
   }
 
   if (typeof expiresAtSec !== "number") {
+    console.debug("[sessionSliding] expiresAtSec is not a number, skipping renew");
     return false;
   }
 
   const remainingMs = expiresAtSec * 1000 - nowMs;
-  if (remainingMs <= 0 || remainingMs > thresholdMs) {
+  const remainingMin = Math.floor(remainingMs / 1000 / 60);
+
+  if (remainingMs <= 0) {
+    console.debug("[sessionSliding] Session already expired, skipping renew");
+    return false;
+  }
+
+  if (remainingMs > thresholdMs) {
     return false;
   }
 
   if (nowMs - lastAttemptAtMs < throttleMs) {
+    console.debug("[sessionSliding] Throttling renewal attempt");
     return false;
   }
 
+  console.info(`[sessionSliding] Attempting sliding session renewal. Remaining: ${remainingMin}m`);
   return true;
 }
 
@@ -60,17 +70,27 @@ export function shouldAttemptUnlimitedSessionRenew({
   }
 
   if (typeof expiresAtSec !== "number") {
+    console.debug("[sessionSliding] expiresAtSec is not a number, skipping unlimited renew");
     return false;
   }
 
   const remainingMs = expiresAtSec * 1000 - nowMs;
-  if (remainingMs <= 0 || remainingMs > thresholdMs) {
+  const remainingMin = Math.floor(remainingMs / 1000 / 60);
+
+  if (remainingMs <= 0) {
+    console.debug("[sessionSliding] Session already expired, skipping unlimited renew");
+    return false;
+  }
+
+  if (remainingMs > thresholdMs) {
     return false;
   }
 
   if (nowMs - lastAttemptAtMs < throttleMs) {
+    console.debug("[sessionSliding] Throttling unlimited renewal attempt");
     return false;
   }
 
+  console.info(`[sessionSliding] Attempting unlimited session renewal. Remaining: ${remainingMin}m`);
   return true;
 }
diff --git a/adminfront/tests/auth.spec.ts b/adminfront/tests/auth.spec.ts
index b74215a5..87e5623b 100644
--- a/adminfront/tests/auth.spec.ts
+++ b/adminfront/tests/auth.spec.ts
@@ -10,7 +10,7 @@ test.describe("Authentication", () => {
         window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean }
       )._IS_TEST_MODE = true;
 
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -45,12 +45,12 @@ test.describe("Authentication", () => {
       if (url.includes(".well-known/openid-configuration")) {
         await route.fulfill({
           json: {
-            issuer: "https://sso.hmac.kr/oidc",
-            authorization_endpoint: "https://sso.hmac.kr/oidc/auth",
-            token_endpoint: "https://sso.hmac.kr/oidc/token",
-            jwks_uri: "https://sso.hmac.kr/oidc/jwks",
-            userinfo_endpoint: "https://sso.hmac.kr/oidc/userinfo",
-            end_session_endpoint: "https://sso.hmac.kr/oidc/session/end",
+            issuer: "http://localhost:5000/oidc",
+            authorization_endpoint: "http://localhost:5000/oidc/auth",
+            token_endpoint: "http://localhost:5000/oidc/token",
+            jwks_uri: "http://localhost:5000/oidc/jwks",
+            userinfo_endpoint: "http://localhost:5000/oidc/userinfo",
+            end_session_endpoint: "http://localhost:5000/oidc/session/end",
           },
           headers: { "Access-Control-Allow-Origin": "*" },
         });
diff --git a/adminfront/tests/bulk_actions.spec.ts b/adminfront/tests/bulk_actions.spec.ts
index 0a3bf8fc..8b0b5e45 100644
--- a/adminfront/tests/bulk_actions.spec.ts
+++ b/adminfront/tests/bulk_actions.spec.ts
@@ -9,7 +9,7 @@ test.describe("Bulk Actions and Tree Search", () => {
         window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean }
       )._IS_TEST_MODE = true;
 
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -114,7 +114,7 @@ test.describe("Bulk Actions and Tree Search", () => {
     });
 
     await page.route("**/oidc/**", async (route) => {
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
   });
 
diff --git a/adminfront/tests/owners.spec.ts b/adminfront/tests/owners.spec.ts
index 77269f11..eea69e9c 100644
--- a/adminfront/tests/owners.spec.ts
+++ b/adminfront/tests/owners.spec.ts
@@ -3,7 +3,7 @@ import { expect, test } from "@playwright/test";
 test.describe("Tenant Owners Management", () => {
   test.beforeEach(async ({ page }) => {
     await page.addInitScript(() => {
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -26,7 +26,7 @@ test.describe("Tenant Owners Management", () => {
     });
 
     await page.route("**/oidc/**", async (route) => {
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
 
     await page.route(/.*\/api\/v1\/.*/, async (route) => {
diff --git a/adminfront/tests/tenants.spec.ts b/adminfront/tests/tenants.spec.ts
index 9dc9e85a..f2b1488e 100644
--- a/adminfront/tests/tenants.spec.ts
+++ b/adminfront/tests/tenants.spec.ts
@@ -9,7 +9,7 @@ test.describe("Tenants Management", () => {
         window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean }
       )._IS_TEST_MODE = true;
 
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -52,7 +52,7 @@ test.describe("Tenants Management", () => {
     });
 
     await page.route("**/oidc/**", async (route) => {
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
   });
 
diff --git a/adminfront/tests/users.spec.ts b/adminfront/tests/users.spec.ts
index ea6fdabb..6633cd5c 100644
--- a/adminfront/tests/users.spec.ts
+++ b/adminfront/tests/users.spec.ts
@@ -3,7 +3,7 @@ import { expect, test } from "@playwright/test";
 test.describe("User Management", () => {
   test.beforeEach(async ({ page }) => {
     await page.addInitScript(() => {
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -33,15 +33,15 @@ test.describe("User Management", () => {
       if (route.request().url().includes("/.well-known/openid-configuration")) {
         return route.fulfill({
           json: {
-            issuer: "https://sso.hmac.kr/oidc",
-            authorization_endpoint: "https://sso.hmac.kr/oidc/auth",
-            token_endpoint: "https://sso.hmac.kr/oidc/token",
-            userinfo_endpoint: "https://sso.hmac.kr/oidc/userinfo",
-            jwks_uri: "https://sso.hmac.kr/oidc/jwks",
+            issuer: "http://localhost:5000/oidc",
+            authorization_endpoint: "http://localhost:5000/oidc/auth",
+            token_endpoint: "http://localhost:5000/oidc/token",
+            userinfo_endpoint: "http://localhost:5000/oidc/userinfo",
+            jwks_uri: "http://localhost:5000/oidc/jwks",
           },
         });
       }
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
 
     await page.route(/.*\/api\/v1\/.*/, async (route) => {
diff --git a/adminfront/tests/users_bulk.spec.ts b/adminfront/tests/users_bulk.spec.ts
index 26107f5b..c7aa3a2d 100644
--- a/adminfront/tests/users_bulk.spec.ts
+++ b/adminfront/tests/users_bulk.spec.ts
@@ -9,7 +9,7 @@ test.describe("Users Bulk Upload", () => {
         window as Window & typeof globalThis & { _IS_TEST_MODE?: boolean }
       )._IS_TEST_MODE = true;
 
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -54,7 +54,7 @@ test.describe("Users Bulk Upload", () => {
     });
 
     await page.route("**/oidc/**", async (route) => {
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
   });
 
diff --git a/adminfront/tests/users_schema.spec.ts b/adminfront/tests/users_schema.spec.ts
index 41f32847..2f954271 100644
--- a/adminfront/tests/users_schema.spec.ts
+++ b/adminfront/tests/users_schema.spec.ts
@@ -3,7 +3,7 @@ import { expect, test } from "@playwright/test";
 test.describe("User Schema Dynamic Form", () => {
   test.beforeEach(async ({ page }) => {
     await page.addInitScript(() => {
-      const authority = "https://sso.hmac.kr/oidc";
+      const authority = "http://localhost:5000/oidc";
       const client_id = "adminfront";
       const key = `oidc.user:${authority}:${client_id}`;
       const authData = {
@@ -35,15 +35,15 @@ test.describe("User Schema Dynamic Form", () => {
       if (route.request().url().includes("/.well-known/openid-configuration")) {
         return route.fulfill({
           json: {
-            issuer: "https://sso.hmac.kr/oidc",
-            authorization_endpoint: "https://sso.hmac.kr/oidc/auth",
-            token_endpoint: "https://sso.hmac.kr/oidc/token",
-            userinfo_endpoint: "https://sso.hmac.kr/oidc/userinfo",
-            jwks_uri: "https://sso.hmac.kr/oidc/jwks",
+            issuer: "http://localhost:5000/oidc",
+            authorization_endpoint: "http://localhost:5000/oidc/auth",
+            token_endpoint: "http://localhost:5000/oidc/token",
+            userinfo_endpoint: "http://localhost:5000/oidc/userinfo",
+            jwks_uri: "http://localhost:5000/oidc/jwks",
           },
         });
       }
-      await route.fulfill({ json: { issuer: "https://sso.hmac.kr/oidc" } });
+      await route.fulfill({ json: { issuer: "http://localhost:5000/oidc" } });
     });
 
     await page.route(/.*\/api\/v1\/.*/, async (route) => {
diff --git a/devfront/tests/helpers/devfront-fixtures.ts b/devfront/tests/helpers/devfront-fixtures.ts
index 39fd3f36..e8200f9b 100644
--- a/devfront/tests/helpers/devfront-fixtures.ts
+++ b/devfront/tests/helpers/devfront-fixtures.ts
@@ -137,11 +137,11 @@ export async function seedAuth(page: Page, role?: string) {
       };
 
       window.localStorage.setItem(
-        "oidc.user:https://sso.hmac.kr/oidc:devfront",
+        "oidc.user:http://localhost:5000/oidc:devfront",
         JSON.stringify(mockOidcUser),
       );
       window.localStorage.setItem(
-        "oidc.user:https://sso.hmac.kr/oidc/:devfront",
+        "oidc.user:http://localhost:5000/oidc/:devfront",
         JSON.stringify(mockOidcUser),
       );
       window.localStorage.setItem("dev_role", injectedRole || "rp_admin");
@@ -155,12 +155,12 @@ export async function seedAuth(page: Page, role?: string) {
     if (url.includes(".well-known/openid-configuration")) {
       await route.fulfill({
         json: {
-          issuer: "https://sso.hmac.kr/oidc",
-          authorization_endpoint: "https://sso.hmac.kr/oidc/auth",
-          token_endpoint: "https://sso.hmac.kr/oidc/token",
-          jwks_uri: "https://sso.hmac.kr/oidc/jwks",
-          userinfo_endpoint: "https://sso.hmac.kr/oidc/userinfo",
-          end_session_endpoint: "https://sso.hmac.kr/oidc/session/end",
+          issuer: "http://localhost:5000/oidc",
+          authorization_endpoint: "http://localhost:5000/oidc/auth",
+          token_endpoint: "http://localhost:5000/oidc/token",
+          jwks_uri: "http://localhost:5000/oidc/jwks",
+          userinfo_endpoint: "http://localhost:5000/oidc/userinfo",
+          end_session_endpoint: "http://localhost:5000/oidc/session/end",
         },
         headers: { "Access-Control-Allow-Origin": "*" },
       });