diff --git a/tox.ini b/tox.ini
index 7ef07329e..d48ff874f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -45,7 +45,7 @@ commands=
 
 [testenv:py33-pexpect]
 changedir=testing
-basepython=python2.7
+basepython=python3.3
 deps={[testenv:py27-pexpect]deps}
 commands=
   py.test -rfsxX test_pdb.py test_terminal.py test_unittest.py