Chassis strength was analyzed support plate the punching, forging a chamfer machining difficult effect on plate stamping forming punch small holes damage form. Including the manufacturing process,a fracture (broken,snap,etc),the longitudinal crack, and deformation analyses, found a stamping punch in punch.It put forward solution in the mold design, material selection, production process, production equipment in order to improve the stamping forming service life of the punch holes, the quality of our products, and the mass production was realized.