diff --git a/paddlenlp/generation/utils.py b/paddlenlp/generation/utils.py
index ffd34b1d79cd..e955331ec7e3 100644
--- a/paddlenlp/generation/utils.py
+++ b/paddlenlp/generation/utils.py
@@ -510,8 +510,9 @@ def update_model_kwargs_for_generation(outputs, model_kwargs, is_encoder_decoder
     @staticmethod
     def update_scores_for_generation(scores, next_scores, length, unfinished_flag):
         # update scores
+        # breakpoint()
 
-        unfinished_scores = (scores * length + next_scores) / (length + 1)
+        unfinished_scores = (scores * paddle.cast(length, scores.dtype) + next_scores) / paddle.cast((length + 1), scores.dtype)
         scores = paddle.where(unfinished_flag, unfinished_scores, scores)
         return scores