diff --git a/python/paddle/fluid/layers/nn.py b/python/paddle/fluid/layers/nn.py
index 00502a5ec79e4c5d397c2a9707e7529b23d6261f..994bef6fba8c35c797aa71ac62b3066e583ea793 100644
--- a/python/paddle/fluid/layers/nn.py
+++ b/python/paddle/fluid/layers/nn.py
@@ -9145,7 +9145,7 @@ def rank(input):
     """
     **Rank Layer**
 
-    Returns the rank of a tensor, which is a 0-D int32 Tensor.
+    Returns the number of dimensions for a tensor, which is a 0-D int32 Tensor.
 
     Args:
         input (Variable): The input variable.