diff --git a/requirements/requirements_doc.txt b/requirements/requirements_doc.txt
index 1cf4c34f..c59bc85b 100644
--- a/requirements/requirements_doc.txt
+++ b/requirements/requirements_doc.txt
@@ -1,4 +1,4 @@
-Sphinx==6.1.3
+Sphinx==5.3.0
 jupyter_sphinx==0.4.0
 numpydoc==1.5.0
 ansys-sphinx-theme==0.8.0