 <p>First you should check if <code>lbName.SelectionMode</code> is <code>ListSelectionMode.Multiple</code></p> <p>then you should the following </p> <pre><code>string names = reader["staffName"].ToString(); string[] selectedName = names.Split(','); lbName.SelectedIndex = -1; foreach (var name in selectedName) { lbName.Items.First(item =&gt; item.Value == name).Selected = true; } </code></pre>