Abstract: Verity method is the latest method to calculate weld fatigue life.In the process of the finite element calculation,node load of weld toe is accordingly converted to the element edge distributive load,thin-shell stress analysis formula is used to solve the structure stress problem of weld toe,and the method that structure stress is insensitive to finite element mesh is reached.Based on the fracture mechanics formula of Paris,it took the equivalent structure stress amplitude as the main parameters of master S-N curve,and the curve equation is deduced.To verify the validity of Verity method,fatigue test and simulation of armored steel T-welded joints is conducted,the results show that Verity method calculating structure stress with the insensitivity characteristics of the element.Computing results according to master S-N curve equation is closer to experimental value.Compared with other traditional weld fatigue assessment methods,Verity method is of high accuracy and obvious advantage.