diff --git a/python/sglang/srt/entrypoints/openai/protocol.py b/python/sglang/srt/entrypoints/openai/protocol.py
index 192852c9a..060e9659a 100644
--- a/python/sglang/srt/entrypoints/openai/protocol.py
+++ b/python/sglang/srt/entrypoints/openai/protocol.py
@@ -654,7 +654,7 @@ class ChatCompletionRequest(BaseModel):
 
         sampling_params = {
             "temperature": get_param("temperature"),
-            "max_new_tokens": self.max_tokens or self.max_completion_tokens,
+            "max_new_tokens": self.max_completion_tokens or self.max_tokens,
             "min_new_tokens": self.min_tokens,
             "stop": stop,
             "stop_token_ids": self.stop_token_ids,