diff --git a/mmengine/runner/runner.py b/mmengine/runner/runner.py
index 345c9418dd167e909e991a0e209c5e7614e70c2d..f9c6c9af5566601413ed437c79a959ddc6818651 100644
--- a/mmengine/runner/runner.py
+++ b/mmengine/runner/runner.py
@@ -2238,7 +2238,6 @@ class Runner:
         Args:
             param_scheduler (dict or list): The original parameter scheduler.
         """  # noqa: E501
-        param_schedulers: Union[dict, list, _ParamScheduler]
         if param_scheduler is None:
             return
         if isinstance(param_scheduler, _ParamScheduler):