diff --git a/python/pyspark/sql/dataframe.py b/python/pyspark/sql/dataframe.py
index edc7ca6f5146f49edb96421c7b2281b413e37970..5cd208bb525a331b2a93f6ac2bd80c71cd5934ca 100644
--- a/python/pyspark/sql/dataframe.py
+++ b/python/pyspark/sql/dataframe.py
@@ -1403,6 +1403,16 @@ class DataFrame(object):
         |null|  null|null|
         +----+------+----+
 
+        >>> df4.na.replace('Alice').show()
+        +----+------+----+
+        | age|height|name|
+        +----+------+----+
+        |  10|    80|null|
+        |   5|  null| Bob|
+        |null|  null| Tom|
+        |null|  null|null|
+        +----+------+----+
+
         >>> df4.na.replace(['Alice', 'Bob'], ['A', 'B'], 'name').show()
         +----+------+----+
         | age|height|name|
@@ -1837,7 +1847,7 @@ class DataFrameNaFunctions(object):
 
     fill.__doc__ = DataFrame.fillna.__doc__
 
-    def replace(self, to_replace, value, subset=None):
+    def replace(self, to_replace, value=None, subset=None):
         return self.df.replace(to_replace, value, subset)
 
     replace.__doc__ = DataFrame.replace.__doc__