diff --git a/docs/requirements.txt b/docs/requirements.txt
index 7a068c1d..4f7cc011 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,4 +1,4 @@
-sphinx>=3.1
+sphinx>=3.1<8
 sphinx-rtd-theme
 sphinx-js
 sphinx-csharp