diff --git a/requirements_dev.txt b/requirements_dev.txt
index 9c6f4bd..b58287a 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -31,7 +31,7 @@ six==1.12.0
 snowballstemmer==1.2.1
 Sphinx==1.8.2
 sphinxcontrib-websupport==1.1.0
-tox==3.5.3
+tox==3.6.0
 urllib3==1.24.1
 virtualenv==16.1.0
 watchdog==0.9.0