diff --git a/requirements/ci.txt b/requirements/ci.txt
index 428138e2..8357a299 100644
--- a/requirements/ci.txt
+++ b/requirements/ci.txt
@@ -1,5 +1,5 @@
 codecov==2.0.9
 docutils
-tox
+tox==2.7.0
 tox-travis
 pygments