diff --git a/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py b/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
index 9fdadf6ac..68f1d658e 100644
--- a/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
+++ b/python/sglang/srt/mem_cache/storage/lmcache/lmc_radix_cache.py
@@ -107,7 +107,7 @@ class LMCRadixCache(RadixCache):
                 "v_buffer",
                 getattr(self.token_to_kv_pool_allocator._kvcache, "v_buffer"),
             ),
-            tp_group=tp_group,
+            tp_group=tp_group.device_group if tp_group is not None else None,
         )
 
         self.load_stream = torch.cuda.Stream()