diff --git a/aiogram/dispatcher/dispatcher.py b/aiogram/dispatcher/dispatcher.py
index 6d16a005..4cd38ce3 100644
--- a/aiogram/dispatcher/dispatcher.py
+++ b/aiogram/dispatcher/dispatcher.py
@@ -299,7 +299,7 @@ class Dispatcher(DataMixin, ContextInstanceMixin):
                     await asyncio.sleep(relax)
 
         finally:
-            self._close_waiter._set_result(None)
+            self._close_waiter.set_result(None)
             log.warning('Polling is stopped.')
 
     async def _process_polling_updates(self, updates, fast: typing.Optional[bool] = True):