XAttribute.IsNamespaceDeclaration Property tells if this attribute is a namespace declaration.
using System; using System.Linq; using System.Xml; using System.Xml.Linq; using System.Collections; using System.Collections.Generic; public class MainClass{ public static void Main(){ XNamespace aw = "http://www.domain.com"; XElement root = new XElement(aw + "Root", new XAttribute(XNamespace.Xmlns + "aw", "http://www.domain.com"), new XAttribute(aw + "Att", "content") ); foreach (XAttribute att in root.Attributes()) { if (att.IsNamespaceDeclaration) Console.WriteLine("{0} is a namespace declaration", att.Name); else Console.WriteLine("{0} is not a namespace declaration", att.Name); } } }