diff --git a/setup.cfg b/setup.cfg
index d04882ae4..882d33307 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -65,7 +65,7 @@ redis =
 workers =
   kombu!=4.0.2,>=4.0.0 # BSD
 eventlet =
-  eventlet!=0.18.3,<0.21.0,>=0.18.2 # MIT
+  eventlet!=0.18.3,!=0.20.1,<0.21.0,>=0.18.2 # MIT
 doc =
   sphinx!=1.6.1,>=1.5.1 # BSD
   oslosphinx>=4.7.0 # Apache-2.0