diff --git a/python/sglang/srt/layers/moe/moe_runner/deep_gemm.py b/python/sglang/srt/layers/moe/moe_runner/deep_gemm.py
index c3ef55650..a814b5d23 100644
--- a/python/sglang/srt/layers/moe/moe_runner/deep_gemm.py
+++ b/python/sglang/srt/layers/moe/moe_runner/deep_gemm.py
@@ -486,7 +486,9 @@ class DeepGemmRunnerCore(MoeRunnerCore):
             **gemm_overlap_args_dict,
         )
         meta_overlap_args = running_state.get("meta_overlap_args", None)
-        if meta_overlap_args is not None:
+        # Returns (block_m, threshold) only with down-gemm overlap, else None;
+        # meta_overlap_args may be set without overlap, so guard the unpack.
+        if meta_overlap_args is not None and deep_gemm_return_value is not None:
             block_m, threshold = deep_gemm_return_value
             meta_overlap_args["block_m"] = block_m
             meta_overlap_args["threshold"] = threshold