diff --git a/python/sglang/srt/models/step3p5.py b/python/sglang/srt/models/step3p5.py
index b3f82b916..b9768c25b 100644
--- a/python/sglang/srt/models/step3p5.py
+++ b/python/sglang/srt/models/step3p5.py
@@ -667,7 +667,6 @@ class Step3p5Model(nn.Module):
     ) -> None:
         super().__init__()
         self.config = config
-        self.padding_idx = config.pad_token_id
         self.vocab_size = config.vocab_size
         self.pp_group = get_pp_group()