diff --git a/README.rst b/README.rst
index f8c744c9..bfc11d78 100644
--- a/README.rst
+++ b/README.rst
@@ -98,7 +98,7 @@ branch.
 Requirements
 ------------
 
-Breathe requires Python 3.6+, Sphinx 3.0+ and Doxygen 1.8+.
+Breathe requires Python 3.6+, Sphinx 4.0+ and Doxygen 1.8+.
 
 Mailing List Archives
 ---------------------
diff --git a/requirements/production.txt b/requirements/production.txt
index e4fe9248..d6add0c9 100644
--- a/requirements/production.txt
+++ b/requirements/production.txt
@@ -2,4 +2,4 @@ docutils>=0.12
 Jinja2>=2.7.3
 MarkupSafe>=0.23
 Pygments>=1.6
-Sphinx>=3.0,<5
+Sphinx>=4.0,<6