diff --git a/setup.py b/setup.py
index 600c90de3..af51e250f 100644
--- a/setup.py
+++ b/setup.py
@@ -32,7 +32,7 @@
     "autoapi",
     "ipython",
     "rstcheck",
-    "sphinx",
+    "sphinx<7",
     "sphinx-argparse",
     "sphinx-autodoc-typehints",
     "sphinx_rtd_theme",