diff --git a/app/Http/Controllers/Api/V1/DepartmentController.php b/app/Http/Controllers/Api/V1/DepartmentController.php
index c761b14..1cfe8ea 100644
--- a/app/Http/Controllers/Api/V1/DepartmentController.php
+++ b/app/Http/Controllers/Api/V1/DepartmentController.php
@@ -9,11 +9,13 @@
 
 class DepartmentController extends Controller
 {
+    public function __construct(private DepartmentService $service) {}
+
     // GET /v1/departments
     public function index(Request $request)
     {
         return ApiResponse::handle(function () use ($request) {
-            return DepartmentService::index($request->all());
+            return $this->service->index($request->all());
         }, '부서 목록 조회');
     }
 
@@ -21,24 +23,23 @@ public function index(Request $request)
     public function store(Request $request)
     {
         return ApiResponse::handle(function () use ($request) {
-            return DepartmentService::store($request->all());
+            return $this->service->store($request->all());
         }, '부서 생성');
     }
 
     // GET /v1/departments/{id}
-    public function show(int $id, Request $request, DepartmentService $service)
+    public function show(int $id, Request $request)
     {
-        return \App\Helpers\ApiResponse::handle(
-            fn() => $service->show($id, $request->all()),
-            '부서 단건 조회'
-        );
+        return ApiResponse::handle(function () use ($id, $request) {
+            return $this->service->show($id, $request->all()); // ✅ 실제 사용하면 경고 사라짐
+        }, '부서 단건 조회');
     }
 
     // PATCH /v1/departments/{id}
     public function update($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::update((int)$id, $request->all());
+            return $this->service->update((int)$id, $request->all());
         }, '부서 수정');
     }
 
@@ -46,7 +47,7 @@ public function update($id, Request $request)
     public function destroy($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::destroy((int)$id, $request->all());
+            return $this->service->destroy((int)$id, $request->all());
         }, '부서 삭제');
     }
 
@@ -54,7 +55,7 @@ public function destroy($id, Request $request)
     public function listUsers($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::listUsers((int)$id, $request->all());
+            return $this->service->listUsers((int)$id, $request->all());
         }, '부서 사용자 목록');
     }
 
@@ -62,7 +63,7 @@ public function listUsers($id, Request $request)
     public function attachUser($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::attachUser((int)$id, $request->all());
+            return $this->service->attachUser((int)$id, $request->all());
         }, '부서 사용자 배정');
     }
 
@@ -70,7 +71,7 @@ public function attachUser($id, Request $request)
     public function detachUser($id, $user, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $user, $request) {
-            return DepartmentService::detachUser((int)$id, (int)$user, $request->all());
+            return $this->service->detachUser((int)$id, (int)$user, $request->all());
         }, '부서 사용자 제거');
     }
 
@@ -78,7 +79,7 @@ public function detachUser($id, $user, Request $request)
     public function setPrimary($id, $user, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $user, $request) {
-            return DepartmentService::setPrimary((int)$id, (int)$user, $request->all());
+            return $this->service->setPrimary((int)$id, (int)$user, $request->all());
         }, '주 부서 설정/해제');
     }
 
@@ -86,7 +87,7 @@ public function setPrimary($id, $user, Request $request)
     public function listPermissions($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::listPermissions((int)$id, $request->all());
+            return $this->service->listPermissions((int)$id, $request->all());
         }, '부서 권한 목록');
     }
 
@@ -94,7 +95,7 @@ public function listPermissions($id, Request $request)
     public function upsertPermission($id, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $request) {
-            return DepartmentService::upsertPermission((int)$id, $request->all());
+            return $this->service->upsertPermission((int)$id, $request->all());
         }, '부서 권한 부여/차단');
     }
 
@@ -102,7 +103,7 @@ public function upsertPermission($id, Request $request)
     public function revokePermission($id, $permission, Request $request)
     {
         return ApiResponse::handle(function () use ($id, $permission, $request) {
-            return DepartmentService::revokePermission((int)$id, (int)$permission, $request->all());
+            return $this->service->revokePermission((int)$id, (int)$permission, $request->all());
         }, '부서 권한 제거');
     }
 }