diff --git a/docs/requirements.txt b/docs/requirements.txt
index 96976fe..ca3f21e 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,4 +1,4 @@
 setuptools >=30.3
-Sphinx ~=3.1
+Sphinx ~=4.0
 sphinx-bootstrap-theme ~=0.7
 semantic-version ~=2.8