diff --git a/requirements_dev.txt b/requirements_dev.txt
index 9ee8642..a42d4c7 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,7 +6,7 @@ flake8==3.7.9
 black==19.10b0
 tox==3.14.2
 coverage==4.5.4
-Sphinx==2.2.2
+Sphinx==3.5.1
 twine==3.1.1
 
 pytest==5.3.1