 <p>I had this same issue. Turns out I needed to traverse the subview tree like so:</p> <pre><code>var subView = alertController.view.subviews.first as! UIView var contentView = subView.subviews.first as! UIView contentView.backgroundColor = UIColor(red: 233.0/255.0, green: 133.0/255.0, blue: 49.0/255.0, alpha: 1.0) </code></pre>