diff --git a/requirements-dev.txt b/requirements-dev.txt
index 4083948c..4a21a3e2 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -9,7 +9,7 @@ unittest2==1.1.0
 selenium==3.141.0
 twine==3.3.0
 Pallets-Sphinx-Themes==1.2.3
-Sphinx==3.4.1
+Sphinx==3.5.1
 sphinx-issues==1.2.0
 sphinx-jinja==1.1.1
 sphinx-tabs==2.0.1