diff --git a/sphinx/ext/doctest.py b/sphinx/ext/doctest.py
index df031d1ce..3a06b3292 100644
--- a/sphinx/ext/doctest.py
+++ b/sphinx/ext/doctest.py
@@ -11,7 +11,6 @@
 """
 from __future__ import absolute_import
 
-import codecs
 import doctest
 import re
 import sys