diff --git a/ecs/jskult-webapp/src/controller/bio_api.py b/ecs/jskult-webapp/src/controller/bio_api.py
index 982ef8d2..2f96408a 100644
--- a/ecs/jskult-webapp/src/controller/bio_api.py
+++ b/ecs/jskult-webapp/src/controller/bio_api.py
@@ -83,7 +83,6 @@ def search_bio_data(
     json_response.set_cookie(
         key='session',
         value=session.session_key,
-        max_age=environment.SESSION_EXPIRE_MINUTE * 60,  # cookieの有効期限は秒数指定なので、60秒をかける
         secure=True,
         httponly=True
     )
@@ -156,7 +155,6 @@ async def download_bio_data(
     json_response.set_cookie(
         key='session',
         value=session.session_key,
-        max_age=environment.SESSION_EXPIRE_MINUTE * 60,  # cookieの有効期限は秒数指定なので、60秒をかける
         secure=True,
         httponly=True
     )
diff --git a/ecs/jskult-webapp/src/router/session_router.py b/ecs/jskult-webapp/src/router/session_router.py
index 9389a722..a4a28e25 100644
--- a/ecs/jskult-webapp/src/router/session_router.py
+++ b/ecs/jskult-webapp/src/router/session_router.py
@@ -123,7 +123,6 @@ class AfterSetCookieSessionRoute(MeDaCaRoute):
         response.set_cookie(
             key='session',
             value=session_key,
-            max_age=environment.SESSION_EXPIRE_MINUTE * 60,  # cookieの有効期限は秒数指定なので、60秒をかける
             secure=True,
             httponly=True
         )