diff --git a/requirements.txt b/requirements.txt
index aaaeaed..2f21530 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
 mongoengine==0.15.0
-mongomock==3.14.0
+mongomock==4.3.0
 coverage==4.5.1