diff --git a/docs/requirements-docs.txt b/docs/requirements-docs.txt
index 096561ad..ad5df58c 100644
--- a/docs/requirements-docs.txt
+++ b/docs/requirements-docs.txt
@@ -6,5 +6,5 @@
 # on sphinx >=1.6, <6.0
 # => The sphix requirement must not be >=6.0
 
-sphinx >=5.0, <10.0
+sphinx >=9.1.0, <10.0
 sphinx-rtd-theme >=1.0, <3.0