diff --git a/vllm/model_executor/layers/sampler.py b/vllm/model_executor/layers/sampler.py
index 7b2a60d266ed5..96d55da851d2e 100644
--- a/vllm/model_executor/layers/sampler.py
+++ b/vllm/model_executor/layers/sampler.py
@@ -1436,7 +1436,8 @@ def _build_sampler_output(
         deferred_sample_results_args=deferred_sample_results_args)
 
 
-def _get_next_prompt_tokens(seq_group: SequenceGroupToSample) -> List[int]:
+def _get_next_prompt_tokens(
+        seq_group: SequenceGroupToSample) -> Tuple[int, ...]:
     """Get a list of next prompt tokens to compute logprob from a
         given sequence group.