diff --git a/requirements_dev.txt b/requirements_dev.txt
index bb4c508..d8e7751 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -3,7 +3,7 @@ bumpversion==0.5.3
 wheel==0.33.6
 watchdog==0.9.0
 flake8==3.7.9
-tox==3.14.2
+tox==3.14.3
 coverage==5.0.1
 Sphinx==2.3.0
 cryptography==2.8