Inverse design is the process of using a certain means of measurement to measure entity or model, and according to the measurements, refactoring physical CAD model through Three-dimensional geometric modeling methods. Basing on the little model, use reverse engineering methods, three-dimensional scanning technology and Raindrop Company produced the inverse engineering software to finish the reverse three-dimensional modeling design of little bear punch. Applying Master CAM to set parameters, simulation run, and automatically generate NC code, in the vertical machining center, complex curved surface NC machining of the model can be finished. In engineering practice, it can improve work efficiency, reduce the labor intensity of product development, and reduce the artificial error of the design.