Abstract: The existing product design system based on case reasoning is analyzed. Aiming at the shortages of the design system that couldn’t depict the function and deed of product design case well, a product design ontology model based on case reasoning is proposed. Product design case ontology and model are established in terms of ontology technologies. According to the characteristics of product design based on case reasoning, the important attributes of ontology model are studied. The search-ing method of product design case provided after product design based on case reasoning is analyzed. In the method the appropriate product design case is searched through EDCOM array and similar degree. In the process of maintenance of on-tology warehouse the method on the integration of ontology is given. Finally a product design prototype system based on case reasoning and ontology technology is developed for auto parts enterprise. Through designing requirement, case searching and other functional models, this system realizes product design based on case reasoning.

Key words: Case searching, Case-based reasoning, Ontology, Similar degree