diff --git a/qlib/contrib/strategy/strategy.py b/qlib/contrib/strategy/strategy.py
index 23e8b5185..74df39f3e 100644
--- a/qlib/contrib/strategy/strategy.py
+++ b/qlib/contrib/strategy/strategy.py
@@ -30,7 +30,7 @@ class BaseStrategy:
 
         Parameters
         -----------
-        score_series : pd.Seires
+        score_series : pd.Series
             stock_id , score.
         current : Position()
             current state of position.