diff --git a/qlib/contrib/model/pytorch_gru.py b/qlib/contrib/model/pytorch_gru.py
index 22c63c539..db8257093 100755
--- a/qlib/contrib/model/pytorch_gru.py
+++ b/qlib/contrib/model/pytorch_gru.py
@@ -56,7 +56,7 @@ class GRU(Model):
         early_stop=20,
         loss="mse",
         optimizer="adam",
-        GPU="0",
+        GPU=0,
         seed=None,
         **kwargs
     ):