diff --git a/requirements.txt b/requirements.txt
index b4c4a274b9..b9c93c69a0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -19,7 +19,7 @@ django-pyscss>=2.0.2 # BSD License (2 clause)
 eventlet>=0.17.4
 httplib2>=0.7.5
 iso8601>=0.1.9
-kombu>=3.0.7
+kombu!=4.0.0,>=3.0.7 # BSD
 netaddr!=0.7.16,>=0.7.12
 oslo.concurrency>=2.3.0 # Apache-2.0
 oslo.config>=2.3.0 # Apache-2.0