diff --git a/doc/requirements.txt b/doc/requirements.txt
index 8aa8ae88f..bfd603edf 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,5 +1,5 @@
-sphinx>=2.0.0,!=2.1.0
-openstackdocstheme>=2.2.1 # Apache-2.0
+sphinx>=2.0.0,!=2.1.0,<=4.2.0
+openstackdocstheme>=2.2.1,<=2.3.1 # Apache-2.0
 
 # API Reference Guide
 os-api-ref>=1.5.0 # Apache-2.0