diff --git a/python/paddle/v2/fluid/tests/test_error_clip.py b/python/paddle/v2/fluid/tests/test_error_clip.py
index 3d6ffe807442f262c24aca1bd08d29d38be457cf..d577d0014dc136ee5ef92155e37009df60d9bf62 100644
--- a/python/paddle/v2/fluid/tests/test_error_clip.py
+++ b/python/paddle/v2/fluid/tests/test_error_clip.py
@@ -43,7 +43,7 @@ prog_clip.block(0).var(hidden1.name).set_error_clip(
 avg_cost_clip = prog_clip.block(0).var(avg_cost.name)
 fluid.backward.append_backward(loss=avg_cost)
 fluid.backward.append_backward(
-    loss=avg_cost_clip, callbacks=fluid.clip.error_clip_callback)
+    loss=avg_cost_clip, callbacks=[fluid.clip.error_clip_callback])
 
 hidden1_grad = prog.block(0).var(hidden1.name + "@GRAD")
 hidden1_grad_clip = prog_clip.block(0).var(hidden1.name + "@GRAD")