Abstract: The electrode life is forecasted by comparing continuous spot welding experiment result with numerical simulation.The increasing rule of electrode diameter with the increase of the number of welding spots can be obtained by continuous spot welding of galvanized steel sheet,and the relative nugget diameter can be computed through ANSYS with different electrode tip diameters.So the relationship between the number of welding spots and nugget diameter can be defined by synthesizing the experiment and the simulation.Based on the definition of the critical nugget diameter,it is possible to forecast the electrode life.The result shows that the error between two methods is no more than 15%.So it can bring some meaningful effect to define the time for repairing and changing electrode in the practical production process.