TreeView TV = new TreeView();//icon addStackPanel sp = new StackPanel();sp.Orientation = Orientation.Horizontal;BitmapImage bmi = new BitmapImage();bmi = new BitmapImage(new Uri("ITEM.png", UriKind.RelativeOrAbsolute));Image img = new Image();img.Source = bmi;img.Height = 15;img.Width = 15;sp.Children.Add(img);TextBlock tb = new TextBlock();tb.Text = "TreeItem";sp.Children.Add(tb);//Add Parent's NodeTreeViewItem item = new TreeViewItem();item.Header = sp;TV.Items.Add(item);