diff --git a/python/sglang/srt/entrypoints/openai/protocol.py b/python/sglang/srt/entrypoints/openai/protocol.py
index 9776cc682..7bf3581cf 100644
--- a/python/sglang/srt/entrypoints/openai/protocol.py
+++ b/python/sglang/srt/entrypoints/openai/protocol.py
@@ -721,7 +721,11 @@ class ChatCompletionRequest(BaseModel):
                 ctk = values.get("chat_template_kwargs")
                 if not isinstance(ctk, dict):
                     ctk = {}
+                # different models check different keys:
+                # - "thinking" for deepseek-v3, kimi_k2
+                # - "enable_thinking" for qwen3, glm45, nemotron_3, interns1, mimo
                 ctk.setdefault("thinking", True)
+                ctk.setdefault("enable_thinking", True)
                 values["chat_template_kwargs"] = ctk
 
         if values.get("reasoning_effort") == "none":
diff --git a/test/registered/unit/entrypoints/openai/test_protocol.py b/test/registered/unit/entrypoints/openai/test_protocol.py
index ee978f6a7..5cd33ecaa 100644
--- a/test/registered/unit/entrypoints/openai/test_protocol.py
+++ b/test/registered/unit/entrypoints/openai/test_protocol.py
@@ -191,7 +191,10 @@ class TestChatCompletionRequest(unittest.TestCase):
             },
         )
         self.assertEqual(request.reasoning_effort, "high")
-        self.assertEqual(request.chat_template_kwargs, {"thinking": True})
+        self.assertEqual(
+            request.chat_template_kwargs,
+            {"thinking": True, "enable_thinking": True},
+        )
 
     def test_chat_completion_reasoning_effort_none(self):
         """Test reasoning_effort='none' disables thinking"""