NdFeB is the third generation of thulium that is most powerful magnet. It is composed of Fe 、 Nd 、 B with high Energy Product and perfect coercive force. Due to the highest magnetic force per unit and easy shaping, NdFeB has been accepted and used widely in many specified macro electronic appearances, automobile and audio facility. But the defects of this material we have to take into consideration. It should be used in low temperature and has relatively weak corruption resistance and easy oxidation. Therefore it should be used in a strict limited scope.