diff --git a/zeroconf.py b/zeroconf.py
index 779aef75..671762b5 100644
--- a/zeroconf.py
+++ b/zeroconf.py
@@ -1069,7 +1069,7 @@ def _set_properties(self, properties):
 
                 if value is None:
                     suffix = b''
-                elif isinstance(value, unicode):
+                elif isinstance(value, unicode) or isinstance(value, str):
                     suffix = value.encode('utf-8')
                 elif isinstance(value, int):
                     if value: