diff --git a/ci/requirements/doc.yml b/ci/requirements/doc.yml
index e4453ac3cf7..be1b073cf1e 100644
--- a/ci/requirements/doc.yml
+++ b/ci/requirements/doc.yml
@@ -13,6 +13,7 @@ dependencies:
   - ipython
   - iris>=2.3
   - jupyter_client
+  - matplotlib-base=3.3.0
   - nbsphinx
   - netcdf4>=1.5
   - numba