diff --git a/pandas/core/index.py b/pandas/core/index.py
index 195cb21d6564c..0eddf701995c4 100644
--- a/pandas/core/index.py
+++ b/pandas/core/index.py
@@ -4014,7 +4014,7 @@ def sortlevel(self, level=0, ascending=True, sort_remaining=True):
         labels = list(self.labels)
         shape = list(self.levshape)
 
-        if isinstance(level, (str, int)):
+        if isinstance(level, (basestring, int)):
             level = [level]
         level = [self._get_level_number(lev) for lev in level]