diff --git a/vllm/entrypoints/generate/beam_search/online.py b/vllm/entrypoints/generate/beam_search/online.py
index 1daef9529be..4d101e9434f 100644
--- a/vllm/entrypoints/generate/beam_search/online.py
+++ b/vllm/entrypoints/generate/beam_search/online.py
@@ -61,6 +61,7 @@ class BeamSearchOnlineMixin(ABC):
             logprobs=logprobs_num,
             max_tokens=1,
             temperature=temperature,
+            detokenize=False,
         )
         all_beams = [
             BeamSearchSequence(