diff --git a/tox.ini b/tox.ini
index d9be7f410..d53d79d5b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,7 +2,7 @@
 minversion=2.0
 distshare={homedir}/.tox/distshare
 envlist=
-     flakes,py26,py27,py33,py34,pypy,
+     flakes,py26,py27,py33,py34,py35,pypy,
      {py27,py34}-{pexpect,xdist,trial},
      py27-nobyte,doctesting,py27-cxfreeze