diff --git a/python/sglang/srt/sampling/penaltylib/min_new_tokens.py b/python/sglang/srt/sampling/penaltylib/min_new_tokens.py
index 692f226e4..c6174de23 100644
--- a/python/sglang/srt/sampling/penaltylib/min_new_tokens.py
+++ b/python/sglang/srt/sampling/penaltylib/min_new_tokens.py
@@ -29,7 +29,11 @@ class BatchedMinNewTokensPenalizer(_BatchedPenalizer):
                         list(
                             (req.sampling_params.stop_token_ids or set())
                             | (req.tokenizer.additional_stop_token_ids or set())
-                            | {req.tokenizer.eos_token_id}
+                            | (
+                                {req.tokenizer.eos_token_id}
+                                if req.tokenizer.eos_token_id is not None
+                                else set()
+                            )
                         )
                     ),
                     dtype=torch.int64,