 <p>If you need <code>Unicode</code> support and you are not able to use the <code>unescape</code> functionality implemented in <code>System.Web</code>, you can use the following replace statement instead:</p> <pre><code>string str = "%u0442%u043E%u0432%u0430%20%u0435%20text%20%14%u20AC"; //replace Unicode characters str = Regex.Replace(str, @"%U([0-9A-F]{4})", match =&gt; ((char)int.Parse( match.Groups[1].Value, NumberStyles.HexNumber ) ).ToString(),RegexOptions.IgnoreCase ); //now replace ASCII character str = Regex.Replace(str, @"%([0-9A-F]{2})", match =&gt; ((char)int.Parse( match.Groups[1].Value, NumberStyles.HexNumber ) ).ToString(),RegexOptions.IgnoreCase ); Console.WriteLine(str); </code></pre>