diff --git a/python/sglang/srt/managers/schedule_batch.py b/python/sglang/srt/managers/schedule_batch.py
index 2c03f8f67..b2ba7348c 100644
--- a/python/sglang/srt/managers/schedule_batch.py
+++ b/python/sglang/srt/managers/schedule_batch.py
@@ -843,7 +843,6 @@ class ScheduleBatch(ScheduleBatchDisaggregationDecodeMixin):
     global_num_tokens_for_logprob: Optional[List[int]] = None
     is_extend_in_batch: bool = False
     can_run_dp_cuda_graph: bool = False
-    is_extend_in_batch: bool = False
     tbo_split_seq_index: Optional[int] = None
     global_forward_mode: Optional[ForwardMode] = None