The influence of rare-earth oxide La2O3, Ceo2 and Y2O3 on the emission ability and stability of tungsten electrode materials were investigated. Three new kinds of RE-W electrode materials were produced by powder metallurgy and metal processing technology. They were compared with one another in respect of the arc starting characterstics and the arc voltage-current characteristics. The La-W, Ce-W, Y-W, and Th-W cathode tip microstructure after arc burning were observed through SEM and EDAX. The action of rare-earth elements and their acting mechanism in the emission process of tungsten electrode were analysed. As it turned out that the La2O3-W electrode, of which w ( La2O3 ) =2.2 % exhibited the best properties when the current is of little or middle volume, and when the cathodes are used in large current,the Y2O3-W electrode is the best.