diff --git a/contrib/inventory/ec2.py b/contrib/inventory/ec2.py
index b8b1d43deac..0208ed1fde5 100755
--- a/contrib/inventory/ec2.py
+++ b/contrib/inventory/ec2.py
@@ -1294,7 +1294,7 @@ class Ec2Inventory(object):
     def to_safe(self, word):
         ''' Converts 'bad' characters in a string to underscores so they can be used as Ansible groups '''
         regex = "[^A-Za-z0-9\_"
-        if self.replace_dash_in_groups:
+        if not self.replace_dash_in_groups:
             regex += "\-"
         return re.sub(regex + "]", "_", word)