diff --git a/ppqi/inference.py b/ppqi/inference.py
index 75dbb6c..63d3170 100644
--- a/ppqi/inference.py
+++ b/ppqi/inference.py
@@ -64,8 +64,10 @@ def load_config(self, modelpath, use_gpu, gpu_id, use_mkldnn, cpu_threads):
                 print(
                     '''Error! Unable to use GPU. Please set the environment variables "CUDA_VISIBLE_DEVICES=GPU_id" to use GPU. Now switch to CPU to continue...''')
                 use_gpu = False
-
-        if os.path.isdir(modelpath):
+                
+        if isinstance(modelpath, Config):
+            config = modelpath
+        elif os.path.isdir(modelpath):
             if os.path.exists(os.path.join(modelpath, "__params__")):
                 # __model__ + __params__
                 model = os.path.join(modelpath, "__model__")
@@ -87,8 +89,6 @@ def load_config(self, modelpath, use_gpu, gpu_id, use_mkldnn, cpu_threads):
             model = modelpath + ".pdmodel"
             params = modelpath + ".pdiparams"
             config = Config(model, params)
-        elif isinstance(modelpath, Config):
-            config = modelpath
         else:
             raise Exception(
                 "Error! Can\'t find the model in: %s. Please check your model path." % os.path.abspath(modelpath))