diff --git a/docs/requirements.txt b/docs/requirements.txt
index 21458a4d6..536d08901 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,5 +1,6 @@
 matplotlib
 pymongo
+progressbar2==3.37.0
 scikit-image
 scipy
 sphinx==1.7.1