diff --git a/src/chongming_database/__init__.py b/src/chongming_database/__init__.py
index e18c02b..43f9bf1 100644
--- a/src/chongming_database/__init__.py
+++ b/src/chongming_database/__init__.py
@@ -25,7 +25,7 @@ class Database:
            expire_on_commit=False
         ) # type: ignore
     
-    def get_session(self):
+    def get_session(self) -> AsyncSession:
         """返回一个异步上下文管理器，用于获取会话"""
         if self._session_maker is None:
             raise RuntimeError("Database not initialized")
@@ -36,4 +36,4 @@ class Database:
         if self._engine:
             await self._engine.dispose()
             self._engine = None
-            self._session_maker = None
\ No newline at end of file
+            self._session_maker = None