diff --git a/share/gitian-updater b/share/gitian-updater
index c736a11..8b3e65d 100755
--- a/share/gitian-updater
+++ b/share/gitian-updater
@@ -61,7 +61,7 @@ def download(url, dest):
         print "Downloading from %s"%(url)
     file_name = url.split('/')[-1]
     u = urllib2.urlopen(url)
-    f = open(dest, 'w')
+    f = open(dest, 'wb')
     meta = u.info()
     file_size = int(meta.getheaders("Content-Length")[0])
     if quiet == 0: