diff --git a/requirements.txt b/requirements.txt
index fc36679020..02fd5a809e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -31,7 +31,7 @@ PyYAML>=3.12 # MIT
 requests>=2.14.2 # Apache-2.0
 six>=1.10.0 # MIT
 stevedore>=1.20.0 # Apache-2.0
-tenacity>=4.4.0  # Apache-2.0
+tenacity>=4.4.0,<7.0.0  # Apache-2.0
 tooz[zake]>=1.47.0 # Apache-2.0
 os-xenapi>=0.3.3 # Apache-2.0
 oslo.cache>=1.26.0 # Apache-2.0