diff --git a/python/pyspark/sql/types.py b/python/pyspark/sql/types.py
index ecb8eb9a2f2f..780c114dff5c 100644
--- a/python/pyspark/sql/types.py
+++ b/python/pyspark/sql/types.py
@@ -536,7 +536,7 @@ def __len__(self):
 
     def __getitem__(self, key):
         """Access fields by name or slice."""
-        if isinstance(key, str):
+        if isinstance(key, basestring):
             for field in self:
                 if field.name == key:
                     return field