diff --git a/python/sglang/srt/layers/logits_processor.py b/python/sglang/srt/layers/logits_processor.py
index 981040d0d..4958c6d04 100644
--- a/python/sglang/srt/layers/logits_processor.py
+++ b/python/sglang/srt/layers/logits_processor.py
@@ -335,13 +335,13 @@ class LogitsProcessor(nn.Module):
                     aux_pruned_states = torch.cat(aux_pruned_states, dim=-1)
                     hidden_states_to_store = (
                         aux_pruned_states[sample_indices]
-                        if sample_indices
+                        if sample_indices is not None
                         else aux_pruned_states
                     )
                 else:
                     hidden_states_to_store = (
                         pruned_states[sample_indices]
-                        if sample_indices
+                        if sample_indices is not None
                         else pruned_states
                     )
             else: