diff --git a/lower-constraints.txt b/lower-constraints.txt
index bddc7c4d..46516212 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -65,7 +65,7 @@ requestsexceptions==1.2.0
 restructuredtext-lint==1.1.1
 six==1.10.0
 snowballstemmer==1.2.1
-Sphinx==1.6.2
+Sphinx==3.4.1
 sphinxcontrib-websupport==1.0.1
 SQLAlchemy-Utils==0.30.11
 SQLAlchemy==1.0.10