diff --git a/python/paddle/fluid/layer_helper.py b/python/paddle/fluid/layer_helper.py
index 86efd1ff51cf29485ee28b4d60ffb1439af1aad9..de752d1daeb6bc725cf6eff1bb74a786e2ad6b95 100644
--- a/python/paddle/fluid/layer_helper.py
+++ b/python/paddle/fluid/layer_helper.py
@@ -68,11 +68,11 @@ class LayerHelper(object):
 
     @property
     def param_attr(self):
-        return ParamAttr.to_attr(self.kwargs.get('param_attr', None))
+        return ParamAttr._to_attr(self.kwargs.get('param_attr', None))
 
     @property
     def bias_attr(self):
-        return ParamAttr.to_attr(self.kwargs.get('bias_attr', None))
+        return ParamAttr._to_attr(self.kwargs.get('bias_attr', None))
 
     def multiple_param_attr(self, length):
         param_attr = self.param_attr
@@ -262,11 +262,11 @@ class LayerHelper(object):
         g_param = self.startup_program.global_block().create_parameter(
             dtype=dtype,
             shape=g_param_shape,
-            **g_param_attr.to_kwargs(with_initializer=False))
+            **g_param_attr._to_kwargs(with_initializer=False))
         v_param = self.startup_program.global_block().create_parameter(
             dtype=dtype,
             shape=v_param_shape,
-            **v_param_attr.to_kwargs(with_initializer=True))
+            **v_param_attr._to_kwargs(with_initializer=True))
         __norm_except_dim(
             x=v_param,
             out=g_param,
@@ -275,9 +275,9 @@ class LayerHelper(object):
 
         # Add weight normalization to main_program
         g_param = self.main_program.global_block().create_parameter(
-            dtype=dtype, shape=g_param_shape, **g_param_attr.to_kwargs())
+            dtype=dtype, shape=g_param_shape, **g_param_attr._to_kwargs())
         v_param = self.main_program.global_block().create_parameter(
-            dtype=dtype, shape=v_param_shape, **v_param_attr.to_kwargs())
+            dtype=dtype, shape=v_param_shape, **v_param_attr._to_kwargs())
         w_param = __weight_normalize(g_param, v_param, dim=attr.dim)
         return w_param
 
@@ -296,11 +296,11 @@ class LayerHelper(object):
 
         if default_initializer is None and attr.initializer is None:
             if is_bias:
-                attr.set_default_bias_initializer()
+                attr._set_default_bias_initializer()
             else:
-                attr.set_default_param_initializer()
+                attr._set_default_param_initializer()
         else:
-            attr.set_default_initializer(default_initializer)
+            attr._set_default_initializer(default_initializer)
 
         # If weight normalization is set, insert extra parameters and ops.
         # Refer to https://arxiv.org/pdf/1602.07868.pdf
@@ -310,9 +310,9 @@ class LayerHelper(object):
             return param
 
         self.startup_program.global_block().create_parameter(
-            dtype=dtype, shape=shape, **attr.to_kwargs(with_initializer=True))
+            dtype=dtype, shape=shape, **attr._to_kwargs(with_initializer=True))
         return self.main_program.global_block().create_parameter(
-            dtype=dtype, shape=shape, **attr.to_kwargs())
+            dtype=dtype, shape=shape, **attr._to_kwargs())
 
     def get_parameter(self, name):
         param = self.main_program.global_block().var(name)
diff --git a/python/paddle/fluid/param_attr.py b/python/paddle/fluid/param_attr.py
index 0a42b9fca8dba7a11b414990be6c04c93158864f..4a61f85ec4b5c5108ded31632af75dbbdaaaba71 100644
--- a/python/paddle/fluid/param_attr.py
+++ b/python/paddle/fluid/param_attr.py
@@ -67,7 +67,7 @@ class ParamAttr(object):
         self.gradient_clip = gradient_clip
         self.model_average = do_model_average
 
-    def set_default_initializer(self, initializer):
+    def _set_default_initializer(self, initializer):
         """
         Set the default initializer, the initializer should be Constant,
         Uniform, Normal, Xavier, MSRA.
@@ -88,7 +88,7 @@ class ParamAttr(object):
 
         self.initializer = initializer
 
-    def set_default_param_initializer(self):
+    def _set_default_param_initializer(self):
         """
         Set the default initializer for the parameter with Xavier.
 
@@ -98,9 +98,9 @@ class ParamAttr(object):
         Returns:
             None.
         """
-        self.set_default_initializer(Xavier())
+        self._set_default_initializer(Xavier())
 
-    def set_default_bias_initializer(self):
+    def _set_default_bias_initializer(self):
         """
         Set the default initializer for the bias with Constant(0.0).
 
@@ -110,10 +110,10 @@ class ParamAttr(object):
         Returns:
             None.
         """
-        self.set_default_initializer(Constant(0.0))
+        self._set_default_initializer(Constant(0.0))
 
     @staticmethod
-    def to_attr(arg):
+    def _to_attr(arg):
         """
         Create ParamAttr[s].
 
@@ -131,7 +131,7 @@ class ParamAttr(object):
         if arg is None:
             return ParamAttr()
         elif isinstance(arg, list) or isinstance(arg, tuple):
-            return [ParamAttr.to_attr(a) for a in arg]
+            return [ParamAttr._to_attr(a) for a in arg]
         elif isinstance(arg, ParamAttr):
             return arg
         elif isinstance(arg, str) or isinstance(arg, unicode):
@@ -141,11 +141,11 @@ class ParamAttr(object):
         elif isinstance(arg, WeightDecayRegularizer):
             return ParamAttr(regularizer=arg)
         elif isinstance(arg, bool):
-            return ParamAttr.to_attr(None) if arg else False
+            return ParamAttr._to_attr(None) if arg else False
         else:
             raise TypeError("{0} cast to ParamAttr".format(type(arg)))
 
-    def to_kwargs(self, with_initializer=False):
+    def _to_kwargs(self, with_initializer=False):
         """
         Returns the attributes of this parameter.