diff --git a/python/sglang/srt/server_args.py b/python/sglang/srt/server_args.py
index dab9ea9ff..e461a6512 100644
--- a/python/sglang/srt/server_args.py
+++ b/python/sglang/srt/server_args.py
@@ -6216,7 +6216,7 @@ class ServerArgs:
                 )
                 self.enable_lmcache = False
 
-        if not self.pp_size > 1:
+        if self.pp_size > 1:
             logger.warning(
                 "Pipeline parallelism is disabled because of using diffusion LLM inference"
             )