diff --git a/python/paddle/fluid/layers/nn.py b/python/paddle/fluid/layers/nn.py
index dd918840c880128bfdbad76a5ebb0f6a5e747164..f6092750e7aa803ec39ba75e06604b93c4bd2a10 100644
--- a/python/paddle/fluid/layers/nn.py
+++ b/python/paddle/fluid/layers/nn.py
@@ -32,8 +32,6 @@ from .. import unique_name
 from functools import reduce
 from .. import core
 from ..imperative import layers
-from .control_flow import equal
-from .ops import square
 
 __all__ = [
     'fc',
@@ -10656,6 +10654,10 @@ def tree_conv(nodes_vector,
     return helper.append_activation(pre_activation)
 
 
+from control_flow import equal
+from ops import square
+
+
 def npair_loss(anchor, positive, labels, l2_reg=0.002):
     '''
   **Npair Loss Layer**
@@ -10693,11 +10695,13 @@ def npair_loss(anchor, positive, labels, l2_reg=0.002):
     labels = reshape(labels, shape=[batch_size, 1], inplace=True)
     labels = expand(labels, expand_times=[1, batch_size])
 
-    labels = equal(labels, transpose(labels, perm=[1, 0])).astype('float32')
+    labels = control_flow.equal(
+        labels, transpose(
+            labels, perm=[1, 0])).astype('float32')
     labels = labels / reduce_sum(labels, dim=1, keep_dim=True)
 
-    l2loss = reduce_mean(reduce_sum(square(anchor), 1)) \
-             + reduce_mean(reduce_sum(square(positive), 1))
+    l2loss = reduce_mean(reduce_sum(ops.square(anchor), 1)) \
+             + reduce_mean(reduce_sum(ops.square(positive), 1))
     l2loss = l2loss * Beta * l2_reg
 
     similarity_matrix = matmul(