Taiwanese IC design house has increased the order amounts to assembly house and testing house in China recently because of the price and the market. The life cycle of electronic products are getting shorter and shorter. As a result, to reduce the cycle of IC design and to increase success of the first design become the priority in IC design house competition. Firstly, the investigation into the process of new product development to the industry value chain of supplier. Next, learning about the essence how IC design house manage packaging house and testing house, which is an important element of choosing supplier. This study use Fuzzy DEMATEL of way to find the most important criteria for IC design house evaluate China's assembly house and testing house and each criterion direct/indirect relationship. This study also hopes for the future of IC design house a useful reference for supplier selection.