It were introduced that the using of cooling holder for molybdenum electrodes, and boosting ways and attentions during boosting holders were pointed out. Furthermore, another two kinds of good cooling holders were introduced. They have not only a removable waterway so as to avoid blockage and thermal shock the advancing process, but also operated in all-electric furnaces in extremely arduous environments. In addition, the erosion in the throat and doghouse corner was introduced in the paper, and author with his experiences analyzed the reason and mechanism and pointed out better solutions.