diff --git a/tensorrt_llm/_torch/attention_backend/sparse/dsa.py b/tensorrt_llm/_torch/attention_backend/sparse/dsa.py
index 1d447a8557d..04e0e46c7a1 100644
--- a/tensorrt_llm/_torch/attention_backend/sparse/dsa.py
+++ b/tensorrt_llm/_torch/attention_backend/sparse/dsa.py
@@ -723,7 +723,8 @@ def __init__(self,
         self.rotary_emb = RotaryEmbedding(
             pos_embd_params.rope,
             head_dim=self.rope_dim,
-            is_neox=pos_embd_params.is_neox,
+            # RoPE in indexer is not interleaved
+            is_neox=True,
         )
 
         self.softmax_scale = self.head_dim**-0.5