diff --git a/requirements_dev.txt b/requirements_dev.txt
index d8e7751..f8f0ebe 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -5,7 +5,7 @@ watchdog==0.9.0
 flake8==3.7.9
 tox==3.14.3
 coverage==5.0.1
-Sphinx==2.3.0
+Sphinx==2.3.1
 cryptography==2.8
 PyYAML==5.2
 pytest==5.3.2