diff --git a/core/routers/chat/routes.py b/core/routers/chat/routes.py
index eba7e0d..3b6c460 100644
--- a/core/routers/chat/routes.py
+++ b/core/routers/chat/routes.py
@@ -24,7 +24,7 @@ from core.base.exceptions import WebsocketTooManyRequests
 
 from . import schema
 from .handlers import socket_manager
-from .services import websocket_callback, get_user_active_direct_chats, get_unread_messages_per_chat
+from .services import websocket_callback, get_user_active_direct_chats, get_unread_messages_per_chat, get_chat
 
 logger = logging.getLogger(__name__)
 
@@ -95,15 +95,10 @@ async def get_single_chat_messages(
         page_size: int = Query(default=15, gt=0, le=200),
         last_read_message_id: int = Query(default=0, ge=0),
 ):
-    db_crud = CRUD(db_session, Chat)
-    chat: Chat | None = await db_crud.get(filters={'guid': chat_guid, 'is_deleted': False})
+    chat: Chat | None = await get_chat(chat_guid, login_user, db_session, is_query_messages=True)
     if not chat:
         raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail='您访问的聊天不存在')
 
-    chat_user_ids = [user.user_id for user in await chat.awaitable_attrs.users]
-    if login_user.user_id not in chat_user_ids:
-        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail='您无权访问此聊天')
-
     # 组装查询条件
     conditions = and_(
         Message.chat_id == chat.id,
diff --git a/core/routers/chat/services.py b/core/routers/chat/services.py
index e31fa10..472078b 100644
--- a/core/routers/chat/services.py
+++ b/core/routers/chat/services.py
@@ -94,18 +94,31 @@ async def get_unread_messages_per_chat(
     return results
 
 
-async def get_chat(chat_guid, login_user: User, db_session: AsyncSession) -> Chat | None:
+async def get_chat(chat_guid, login_user: User, db_session: AsyncSession,
+                   is_query_messages: bool = False) -> Chat | None:
     subquery = (
         select(ChatParticipant.chat_id)
-        .where(ChatParticipant.user_id == login_user.user_id)
+        .where(
+            and_(
+                ChatParticipant.user_id == login_user.user_id,
+                ChatParticipant.is_deleted == False
+            )
+        )
     ).scalar_subquery()
 
+    conditions = [
+        Chat.id.in_(subquery),
+        Chat.guid == chat_guid
+    ]
+    if is_query_messages is False:
+        conditions.append(
+            Chat.is_deleted == False
+        )
+
     query = (
         select(Chat)
         .where(and_(
-            Chat.id.in_(subquery),
-            Chat.guid == chat_guid,
-            Chat.is_deleted == False
+            *conditions
         ))
     )
     result = await db_session.execute(query)