diff --git a/.github/workflows/ubuntu-main.yml b/.github/workflows/ubuntu-main.yml
index c587c94a..83e17077 100644
--- a/.github/workflows/ubuntu-main.yml
+++ b/.github/workflows/ubuntu-main.yml
@@ -34,6 +34,14 @@ jobs:
         sudo apt-get install -y doxygen
         echo "::endgroup"
 
+        echo "::group::install sphinx
+        sudo apt-get install -y python3-sphinx
+        echo "::endgroup"
+
+        echo "::group::install sphinx readthedocs theme"
+        sudo apt-get install -y python3-sphinx-rtd-theme
+        echo "::endgroup"
+
         #echo "::group::install pybind11"
         #sudo apt-get install -y pybind11-dev
         #echo "::endgroup"