diff --git a/setup.py b/setup.py
index 7a8d191..1d8dd0b 100644
--- a/setup.py
+++ b/setup.py
@@ -33,7 +33,7 @@
 
 extra_dependencies = {
     "docs": [
-        "sphinx<3.0.0",
+        "sphinx<6.1.4",
         "sphinx-rtd-theme",
         "sphinxcontrib-apidoc",
         "sphinxcontrib-plantuml",