diff --git a/requirements.txt b/requirements.txt
index f1d92a5dae0..8d19e2e2830 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,7 +17,7 @@ requests==2.32.5
 rst2pdf==0.104
 smartypants==2.0.2
 snowballstemmer==3.0.1
-Sphinx==8.1.3
+Sphinx==9.1.0
 sphinx-copybutton==0.5.2
 sphinx-rtd-theme==3.1.0
 sphinx-rtd-dark-mode==1.3.0