Abstract: Aiming at the problem such as thinning and springback in hot stamping process of U-shaped part, numerical simulation analysis was conducted for the hot stamping process of U-shaped part by using the finite element simulation platform DEFORM-3D to analyze the evolution of equivalent stress, strain in different stamping periods and the causes of stamping defects such as thinning and springback. The results show that the equivalent stress, equivalent strain, thinning amount and other parameters are the largest at the round corner, followed by the adjacent waist and legs, and they increase with the increase of temperature, and the value of the legs far from the round corner is very small, similar to rigid body motion,and the effect of temperature can be ignored; the leg rebound is roughly divided into two sections, the lower part of the two legs rotates inward, and the upper part of the two legs rotates outward, the waist rotates upward, and the higher the temperature, the greater the rotation angle. The research results have important guiding significance to improve the hot stamping quality of U-shaped part.