diff --git a/app/views/layouts/base.html.erb b/app/views/layouts/base.html.erb
index 6c5a9b264..204cdb614 100644
--- a/app/views/layouts/base.html.erb
+++ b/app/views/layouts/base.html.erb
@@ -4,7 +4,7 @@
 <meta charset="utf-8" />
 <meta http-equiv="X-UA-Compatible" content="IE=edge"/>
 <title><%= html_title %></title>
-<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
+<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
 <meta name="description" content="<%= Redmine::Info.app_name %>" />
 <meta name="keywords" content="issue,bug,tracker" />
 <%= csrf_meta_tag %>