diff --git a/dev-requirements.txt b/dev-requirements.txt
index 729e2d81..2c4e3d69 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -37,6 +37,6 @@ singledispatch==3.4.0.3
 six==1.11.0
 smmap2==2.0.5
 stevedore==1.30.0
-tox==3.4.0
+tox==3.5.3
 virtualenv==16.0.0
 wrapt==1.10.11