In order to solve the problems of cracking and thinning of upper subframe parts on a certain vehicle during the die trial stage, the mechanical properties, microstructure and formability of hot-rolled high-strength steel QStE420TM were tested by tensile test, electron backscattered diffraction (EBSD) test and Nakazima test, respectively. The results show that the tensile strength of hot-rolled high-strength steel in the rolling direction is 577 MPa, the yield ratio is 0.83 and the elongation is 26.4%. In addition, in order to clarify the anisotropy of the material, work hardening index n and coefficient of anisotropy r after stretching in different directions are calculated. The stamping process of upper subframe parts for hot-rolled high-strength steel QStE420TM is simulated and calculated. The simulation results show that the reason for the cracking of the original produced parts is that the setting of pre-punched hole causes stress concentration at the edge of hole which leads to cracking. Therefore, after canceling the pre-punched hole, the local deformation amount of the second-station process can be reduced by appropriately adjusting the first-station die surface, increasing the radius of die fillet and the pre-forming depth of the first-station process, so that the maximum thinning rate of the final part is reduced from 27.5% to 19%, reducing the risk of stamping cracking of parts.