diff --git a/requirements_dev.txt b/requirements_dev.txt
index 0724f23..c2d8799 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,6 +1,6 @@
 flake8
 tox
 coverage
-Sphinx
+Sphinx==6.1.3
 PyYAML
 pytest