diff --git a/tox.ini b/tox.ini
index 4b61f0e..01badc4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 minversion = 2.0
-envlist = py35-constraints,py27-constraints,pep8-constraints
+envlist = py36-constraints,py35-constraints,py27-constraints,pep8-constraints
 skipsdist = True
 
 [testenv]