Abstract: In order to investigate the selection of the hardening criterion in calculation of welding residual stress, taking an U-shaped rib stiffened plate as the object, the welding residual stress was measured by using the blind-hole method. The welding residual stresses in the plate were calculated by using the isotropic hardening criterion and kinematic hardening criterion respectively based on the thermal elastic-plastic FEM. And the calculated values and the measurement values of the welding residual stress were compared and analyzed. The results show that both the isotropic hardening and the kinematic hardening can reflect the characteristic of the welding residual stress, i.e. tensile stress in the weld area and compressive stress away from the weld; in the weld area, the isotropic hardening greatly overestimated the peak value of welding tensile residual stress, and the calculated result of the kinematic hardening is more accurate, which is slightly lower than the tested residual stress value; in the area away from the weld, the calculated value of welding compressive residual stress is slightly bigger by using the isotropic hardening, and the stress calculated by the kinematic hardening is closer to the tested values. Therefore, it is recommended that the kinematic hardening should be chosen for the calculation of welding residual stress.