diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 49129b19..f89031d3 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -4,7 +4,7 @@ sphinx:
   configuration: doc/source/conf.py
 
 python:
-  version: 3.9
+  version: 3.8
   install:
     - method: pip
       path: .