This paper presents a study on the development of expert design system based on a 3D CAD system customized for the draw die in automotive industry. The proposed system supports die design process efficiently and systematically by utilizing standard data, and design knowledge. The standard data and design knowledge of draw die have been collected and accumulated through the interview with design experts working in the Korean motor company. This paper describes a methodology for systematic die design, automatic checking of dimensions and implementation. The expert design system is being developed based on the product data. All components of the die are regarded as product data and the components are regarded as the unit of die. Parametric design using knowledge base and standard database are introduced for dealing with various and complicated design knowledge easily. For implementation, the expert system is programmed with C and Motif and the system can be linked with CATIA