diff --git a/serve/mlc_serve/engine/engine_common.py b/serve/mlc_serve/engine/engine_common.py
index f8936ea9b7..25744f144f 100644
--- a/serve/mlc_serve/engine/engine_common.py
+++ b/serve/mlc_serve/engine/engine_common.py
@@ -98,7 +98,7 @@ def update_sequence(
     gen_seq.next_start_position = len(prompt_token_ids) + len(gen_seq.generated_token_ids)
     gen_seq.generated_token_ids.extend(new_token_ids)
 
-    delta = gen_seq.text_streamer.put([new_token_ids[-1]])
+    delta = gen_seq.text_streamer.put([gen_seq.generated_token_ids[-1]])
     gen_seq.output_text += delta
 
     gen_seq.output_text, delta, gen_seq.is_finished = check_stopping_sequences(