diff --git a/.ci/build_doc.sh b/.ci/build_doc.sh
index 1867d67d0fde2c6e15b63eb3f0296d86af72d416..7aa453b19b873e9761ea8ce04d9f07b34dbb6f42 100644
--- a/.ci/build_doc.sh
+++ b/.ci/build_doc.sh
@@ -2,5 +2,6 @@
 
 set -e
 
+pip install -r requirements-dev.txt
 python setup.py doc
 mv doc/html doc/"$CI_COMMIT_REF_NAME"