diff --git a/setup.py b/setup.py
index 8cf983d9..4bd7d10c 100644
--- a/setup.py
+++ b/setup.py
@@ -40,7 +40,7 @@
     ],
     extras_require={
         "docs": [
-            "sphinx>=8,<8.3",
+            "sphinx>=9,<9.2",
             "sphinx-rtd-theme>=3,<3.2",
             "myst-parser>=5,<5.1",
             "watchdog>=6,<6.1",