Abstract: Based on the experiment,the characteristic of the wear of the electrode is discussed. The dynamic electric parameters were collected by an automatic data acquisition system,combined with physical phenomena during spot welding. The results indicated that controlling modes affects the life and burning process of the electrode tips during the continuous welding process. Resistance change has a significant correspondence with the electrode burning process. The inflection time of the resistance curve reflects the penetration of the electrode tips into different burning stages. The change of the resistance value of the electrode tips will cause the change of heat generation,so that the burning speed of the electrode tips of different control modes is greatly different.