This paper proposes how to develop the EC(Electronic Commerce) for industrial-related items, which has not been tried yet in EC areas. Usually industrial design derives an idea and concept for a new product from the needs of end-users and manufacturers. Then this product is developed through the design process such as idea-sketch, rendering, and design modeling mock-up. The purpose of this paper is to vitalize the trade for some items which are necessary for the design process and are intermediate products. That is, the idea and concept from the needs and seeds can be dealt with as one item. Furthermore, the idea-sketch and rendering materializing from the idea can be an item also. By doing so, excellent design items which could be thrown away in the middle of the process can be made into valuable commodities. Then we can specify the role of Designer, Manufacturer, and End-User as a buyer or a seller.