The ring-pull can die was chosen as a prototype structure, a system structure of cold stamping die design system based on knowledge engineering was proposed. The object-oriented design idea and foreground-background separation ideas were applied. The arrangement of the system structure and the software topology were designed by means of tiers design method. Based on the reasoning technology of instance, the change design on the original exist die structure can be done quickly combining with the knowledge stored in the knowledge base, and then realize intelligence and digital of design process can be realized. The die design time can be reduced greatly, the competitiveness ability of the enterprise market will be enhanced. The design system software ran well.