diff --git a/python/sglang/jit_kernel/flash_attention/cute/interface.py b/python/sglang/jit_kernel/flash_attention/cute/interface.py
index 10bcd6220..01e53dba1 100644
--- a/python/sglang/jit_kernel/flash_attention/cute/interface.py
+++ b/python/sglang/jit_kernel/flash_attention/cute/interface.py
@@ -1364,6 +1364,7 @@ class FlashAttnVarlenFunc(torch.autograd.Function):
             pack_gqa=pack_gqa,
             score_mod=score_mod,
             aux_tensors=aux_tensors,
+            return_lse=True,
         )
         ctx.save_for_backward(q, k, v, out, lse, cu_seqlens_q, cu_seqlens_k, seqused_q, seqused_k)
         ctx.softmax_scale = softmax_scale