diff --git a/requirements.txt b/requirements.txt
index 61f0e761..46442846 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,6 +25,6 @@ tornado>=4.5.3 # Apache-2.0
 futures>=3.0.0;python_version=='2.7' or python_version=='2.6' # BSD
 # NOTE(sdague): before allowing in >= 0.21 please be sure
 # https://github.com/eventlet/eventlet/issues/401 is resolved
-eventlet!=0.18.3,!=0.20.1,<0.21.0,>=0.18.2 # MIT
+eventlet!=0.18.3,!=0.20.1,>=0.18.2 # MIT
 keystoneauth1>=3.3.0 # Apache-2.0
 monasca-common>=2.7.0 # Apache-2.0