diff --git a/jwtauth/test/test_authentication.py b/jwtauth/test/test_authentication.py
index d112fca..3898c44 100644
--- a/jwtauth/test/test_authentication.py
+++ b/jwtauth/test/test_authentication.py
@@ -18,7 +18,9 @@ def api_client():
     """
     API 클라이언트를 생성하여 반환합니다.
     """
-    return APIClient()
+    client = APIClient()
+    client.default_format = "json"
+    return client
 
 
 @pytest.fixture
@@ -140,8 +142,8 @@ def test_JWT_인증_실패_만료된_토큰(api_client, user):
     url = reverse("refresh")
     # When: 리프레시 API에 만료된 토큰과 함께 POST 요청을 보냄
     response = api_client.post(url)
-    # Then: 응답 상태 코드가 400 (Bad Request)임
-    assert response.status_code == status.HTTP_400_BAD_REQUEST
+    # Then: 응답 상태 코드가 401 (Unauthorized)임
+    assert response.status_code == status.HTTP_401_UNAUTHORIZED
 
 
 @pytest.mark.django_db
@@ -152,8 +154,8 @@ def test_JWT_인증_실패_유효하지_않은_토큰(api_client):
     url = reverse("refresh")
     # When: 리프레시 API에 유효하지 않은 토큰과 함께 POST 요청을 보냄
     response = api_client.post(url)
-    # Then: 응답 상태 코드가 400 (Bad Request)임
-    assert response.status_code == status.HTTP_400_BAD_REQUEST
+    # Then: 응답 상태 코드가 401 (Unauthorized)임
+    assert response.status_code == status.HTTP_401_UNAUTHORIZED
 
 
 @pytest.mark.django_db
diff --git a/weaverse/settings.py b/weaverse/settings.py
index f4647f4..adf14f7 100644
--- a/weaverse/settings.py
+++ b/weaverse/settings.py
@@ -58,12 +58,16 @@
 ]
 
 REST_FRAMEWORK = {
-    "DEFAULT_RENDERER_CLASSES": (
+    "DEFAULT_RENDERER_CLASSES": [
         "rest_framework.renderers.JSONRenderer",
-        "rest_framework.renderers.BrowsableAPIRenderer",  # 이 옵션이 있어야 브라우저에서 API를 시각적으로 볼 수 있음
-    ),
-    "DEFAULT_AUTHENTICATION_CLASSES": ("jwtauth.authentication.JWTAuthentication",),
-    "DEFAULT_PARSER_CLASSES": ("rest_framework.parsers.JSONParser",),
+        "rest_framework.renderers.BrowsableAPIRenderer",
+    ],
+    "DEFAULT_AUTHENTICATION_CLASSES": [
+        "jwtauth.authentication.JWTAuthentication",
+    ],
+    "DEFAULT_PARSER_CLASSES": [
+        "rest_framework.parsers.JSONParser",
+    ],
     "DEFAULT_SCHEMA_CLASS": "drf_spectacular.openapi.AutoSchema",
     "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.PageNumberPagination",
     "PAGE_SIZE": 10,