diff --git a/.readthedocs.yml b/.readthedocs.yml
index 77c2388..6c0a72a 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -2,3 +2,6 @@ requirements_file: .readthedocs.requirements.txt
 
 # conda:
 #     file: docs/environment.yml
+
+python:
+  version: 3.6