diff --git a/pyproject.toml b/pyproject.toml
index 9e65c5fa..099fd3ec 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -38,7 +38,7 @@ dependencies = [
     "markdown-it-py~=4.0",
     "mdit-py-plugins~=0.5",
     "pyyaml",
-    "sphinx>=8,<9",
+    "sphinx>=8,<10",
 ]
 
 [project.urls]