diff --git a/doc/source/requirements.txt b/doc/source/requirements.txt
index 715f2c3d3..9044d840b 100644
--- a/doc/source/requirements.txt
+++ b/doc/source/requirements.txt
@@ -2,7 +2,7 @@ pip
 wheel
 requests>=2.28.1
 
-sphinx==8.0.2
+sphinx==7.4.7
 sphinx-gallery>=0.14.0
 sphinx-rtd-theme>=1.3.0
 pydoctor>=23.4.0
diff --git a/scripts/mkdoc.sh b/scripts/mkdoc.sh
index f4090eceb..db6487d98 100755
--- a/scripts/mkdoc.sh
+++ b/scripts/mkdoc.sh
@@ -51,11 +51,11 @@ if [ ! -d ".venv" ]; then
 
   # Install sphinx, matplotlib, pandas, scipy, wheel and pydoctor into the venv.
   # doc2dash is optional; it will be installed when -d is given
-  .venv/bin/pip install -U pip wheel sphinx==8.0.2 matplotlib pandas scipy pydoctor sphinx-rtd-theme
+  .venv/bin/pip install -U pip wheel sphinx==7.4.7 matplotlib pandas scipy pydoctor sphinx-rtd-theme
 fi
 
 # Make sure that Sphinx, PyDoctor (and maybe doc2dash) are up-to-date in the virtualenv
-.venv/bin/pip install -U sphinx==8.0.2 pydoctor sphinx-gallery sphinxcontrib-jquery sphinx-rtd-theme
+.venv/bin/pip install -U sphinx==7.4.7 pydoctor sphinx-gallery sphinxcontrib-jquery sphinx-rtd-theme
 if [ x$DOC2DASH = x1 ]; then
     .venv/bin/pip install -U doc2dash
 fi