diff --git a/model.py b/model.py
index 3a32bff3212f826d519fa873442e064c0c337385..ae11bdcbc79d038db17e0e2c5ccb2c499b8e4fde 100644
--- a/model.py
+++ b/model.py
@@ -80,7 +80,7 @@ class StaticGraphAdapter(object):
         self._startup_prog = fluid.default_startup_program()
         self._orig_prog = fluid.default_main_program()
 
-        self._label_vars = None  # label variables
+        self._label_vars = {}  # label variables
         self._endpoints = {}
         self._loss_endpoint = None
         self._executor = None
@@ -226,7 +226,7 @@ class StaticGraphAdapter(object):
             if inputs[idx] is not None:
                 feed[n] = inputs[idx]
         if labels is not None:
-            for idx, v in enumerate(self._label_vars):
+            for idx, v in enumerate(self._label_vars[self.mode]):
                 feed[v.name] = labels[idx]
 
         endpoints = self._endpoints[self.mode]
@@ -264,8 +264,8 @@ class StaticGraphAdapter(object):
                     loss_fn = getattr(fluid.layers, l)
                     loss = loss_fn(o, label_var)
                     losses.append(fluid.layers.reduce_mean(loss) * w)
+                self._label_vars[self.mode] = label_vars
                 if self.mode == 'train':
-                    self._label_vars = label_vars
                     self._loss_endpoint = fluid.layers.sum(losses)
                     self.model._optimizer.minimize(self._loss_endpoint)
         self._progs[self.mode] = prog