In this paper, we examined the trend information collected by apparel industries to develop fashionable products. We also investigated the product development process of a swimwear industry, ELLE Swimwear, through in-depth interviews. The results are as follows; 1. The apparel industries were collecting information about a fashion trend, international exhibitions and fairs, world collections, and a market trend to develop fashionable products. 2. As the swimwear consumers are spreaded in all ages, the launching of more specialized swimwear brand with ages is required. 3. These days, swimwear is not only an item of sportswear but also being a fashionable product on street. Therefore, the industries should try to develop a various assortment of swimwear capable of coordinating with multi-mix instead of developing a separate item. 4. To design and produce swimwear satisfying functional, sensual and cultural performance, the development of new materials and patterns are required. 5. Nurturing of swimwear pattern specialists dealing with CAD is urgently required. 6. Turning of understanding about the importance of VMD and more attractive marketing strategies by a specialized team are also required.