Abstract: The influencing factors of shear stress in the stamping shear process were preliminarily analyzed, and the shear rate and relative gap were controllable external factors. The influence of shear rate and relative gap on shear stress was verified by shear test with material universal testing machine. The shear tests of three kinds of parts were carried out at three kinds of shear rates and two kinds of relative gaps. The results show that the shear stress increased with the increase of shear rate. The shear stress decreased with the increase of relative gap.