diff --git a/dssm/infer.py b/dssm/infer.py
index 9192d7e19af10da9edba5353747e11ab6c786f0f..bf5abb0a8d75bd5b4610c22ece89d53b60cc09a6 100644
--- a/dssm/infer.py
+++ b/dssm/infer.py
@@ -94,7 +94,7 @@ class Inferer(object):
     def __init__(self, param_path):
         logger.info("create DSSM model")
 
-        cost, prediction, label = DSSM(
+        prediction = DSSM(
             dnn_dims=layer_dims,
             vocab_sizes=[
                 len(load_dic(path))
@@ -104,7 +104,8 @@ class Inferer(object):
             model_arch=args.model_arch,
             share_semantic_generator=args.share_network_between_source_target,
             class_num=args.class_num,
-            share_embed=args.share_embed)()
+            share_embed=args.share_embed,
+            is_infer=True)()
 
         # load parameter
         logger.info("load model parameters from %s" % param_path)
diff --git a/dssm/network_conf.py b/dssm/network_conf.py
index 430db232db7734368d1261adcaef87a1360c0f28..7be413fcc0d2c41d318015e580741333403e40ff 100644
--- a/dssm/network_conf.py
+++ b/dssm/network_conf.py
@@ -219,7 +219,7 @@ class DSSM(object):
             # but this operator is not supported currently.
             # so AUC will not used.
             return cost, None, label
-        return None, [left_score, right_score], label
+        return right_score
 
     def _build_classification_or_regression_model(self, is_classification):
         '''
@@ -275,4 +275,4 @@ class DSSM(object):
 
         if not self.is_infer:
             return cost, prediction, label
-        return None, prediction, label
+        return prediction