diff --git a/tox.ini b/tox.ini
index 3cf7fa47..23a5ab17 100644
--- a/tox.ini
+++ b/tox.ini
@@ -27,6 +27,7 @@ commands =
     {toxinidir}/tools/setup-etcd-env.sh pifpaf -e OSLO_CACHE_TEST run etcd --  python setup.py testr --slowest --testr-args='functional.*'
 
 [testenv:pep8]
+basepython = python3
 deps =
   -r{toxinidir}/test-requirements.txt
 commands =