diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a1e8a9cd3f03949fcd0cf0f307ef7f324438899f..e5b86a753e5902149aa1e557ff45cb923c6a4733 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -41,6 +41,7 @@ docs:
   script:
     - zypper --non-interactive install python3-pip
     - pip install --upgrade pip
+    - pip install --upgrade sphinx==3.4.3
     - pip install --no-cache-dir -r requirements.txt
     - pip install --no-cache-dir -r requirements_for_documentation.txt
     - chmod +x ./CI/create_documentation.sh