The electrode fixed element of the invention is closed at two ends of a glass tube through a glass bead, comprising an electrode, a closing pin and an external lead. The closing pin joints the jointing surface of the closing pin and the electrode as the same surface through low-melting jointing materials made of metal materials with a melting point of below 1800 degrees centigrade. The closing pin can be formed by metal materials identical to the electrode, with a melting point of above 2000 degrees centigrade. Heat produced by electrode when lightened can be emitted efficiently by adopting the electrode fixed element.