diff --git a/python/sglang/srt/layers/quantization/gptq.py b/python/sglang/srt/layers/quantization/gptq.py
index b52c0575686..af917a26df3 100644
--- a/python/sglang/srt/layers/quantization/gptq.py
+++ b/python/sglang/srt/layers/quantization/gptq.py
@@ -37,6 +37,14 @@ class scalar_types:
 logger = logging.getLogger(__name__)
 
 
+def check_marlin_format(hf_quant_cfg: Dict[str, Any]) -> bool:
+    # compat: gptqmodel and autogptq (eol) main use checkpoint_format: str
+    # compat: autogptq <=0.7.1 is_marlin_format: bool
+    return hf_quant_cfg.get("checkpoint_format") == "marlin" or hf_quant_cfg.get(
+        "is_marlin_format", False
+    )
+
+
 class GPTQConfig(QuantizationConfig):
     """Config class for GPTQ.
 
@@ -262,13 +270,15 @@ def from_config(cls, config: Dict[str, Any]) -> "GPTQMarlinConfig":
 
     @classmethod
     def override_quantization_method(cls, hf_quant_cfg, user_quant) -> Optional[str]:
+        is_marlin_format = check_marlin_format(hf_quant_cfg)
+
         can_convert = cls.is_gptq_marlin_compatible(hf_quant_cfg)
 
         is_valid_user_quant = (
             user_quant is None or user_quant == "marlin" or user_quant == "gptq_marlin"
         )
 
-        if can_convert and is_valid_user_quant:
+        if not is_marlin_format and can_convert and is_valid_user_quant:
             msg = (
                 "The model is convertible to {} during runtime."
                 " Using {} kernel.".format(cls.get_name(), cls.get_name())
@@ -276,7 +286,7 @@ def override_quantization_method(cls, hf_quant_cfg, user_quant) -> Optional[str]
             logger.info(msg)
             return cls.get_name()
 
-        if can_convert and user_quant == "gptq":
+        if not is_marlin_format and can_convert and user_quant == "gptq":
             logger.info(
                 "Detected that the model can run with gptq_marlin"
                 ", however you specified quantization=gptq explicitly,"
@@ -401,11 +411,7 @@ def from_config(cls, config: Dict[str, Any]) -> "MarlinConfig":
 
     @classmethod
     def override_quantization_method(cls, hf_quant_cfg, user_quant) -> Optional[str]:
-        # compat: autogptq >=0.8.0 use checkpoint_format: str
-        # compat: autogptq <=0.7.1 is_marlin_format: bool
-        is_marlin_format = hf_quant_cfg.get(
-            "checkpoint_format"
-        ) == "marlin" or hf_quant_cfg.get("is_marlin_format", False)
+        is_marlin_format = check_marlin_format(hf_quant_cfg)
 
         is_valid_user_quant = (
             user_quant is None or user_quant == "gptq" or user_quant == "marlin"