From the point of view of Knowledge-based Engineering, the knowledge expression, the knowledge organizing format, the knowledge base and management system is researched aiming at the characteristic of motor total design and the knowledge. The knowledge of motor concept design is expressed and organized by Object Oriented method, and the blocking knowledge base is built. Base on the academic research, the Object Oriented knowledge base and its management system for motor intelligent design platform are developed. The result indicates this knowledge base can effectively express the motorcycle knowledge, and make reasoning simply.