diff --git a/python/paddle/fluid/layers/ops.py b/python/paddle/fluid/layers/ops.py
index 636e83996f005c016a2e13f8abbf292960cd9ab0..87a4e32748809f592fc963aab99ecc22d5b6420f 100644
--- a/python/paddle/fluid/layers/ops.py
+++ b/python/paddle/fluid/layers/ops.py
@@ -86,9 +86,9 @@ def uniform_random(shape, dtype='float32', min=-1.0, max=1.0, seed=0):
             result = fluid.layers.uniform_random(shape=[32, 784])
     """
 
-    locals_var = locals()
     if not isinstance(dtype, core.VarDesc.VarType):
         dtype = convert_np_dtype_to_dtype_(dtype)
+    locals_var = locals()
     kwargs = dict()
     for name, val in locals_var.items():
         if val is not None: