diff --git a/qwen3_6_scripts/model_runner.py b/qwen3_6_scripts/model_runner.py
index 3c4f65a3..e4eba0d1 100644
--- a/qwen3_6_scripts/model_runner.py
+++ b/qwen3_6_scripts/model_runner.py
@@ -837,7 +837,7 @@ class ModelInputForGPUBuilder(ModelRunnerInputBuilderBase[ModelInputForGPU]):
 
         cuda_graph_pad_size = self._get_cuda_graph_pad_size(
             num_seqs=len(seq_lens),
-            max_decode_seq_len=max_encoder_seq_len,
+            max_decode_seq_len=max_decode_seq_len,
             max_encoder_seq_len=max_encoder_seq_len)
 
         batch_size = len(input_tokens)