diff --git a/Formula/zbar.rb b/Formula/zbar.rb
index 14d9bf7ac1c..919e6259410 100644
--- a/Formula/zbar.rb
+++ b/Formula/zbar.rb
@@ -5,6 +5,7 @@ class Zbar < Formula
   url 'http://downloads.sourceforge.net/project/zbar/zbar/0.10/zbar-0.10.tar.bz2'
   sha1 '273b47c26788faba4325baecc34063e27a012963'
 
+  depends_on :x11
   depends_on 'pkg-config' => :build
   depends_on 'jpeg'
   depends_on 'imagemagick'