According to the instant demand coming from the collaborative product development of small and medium manufacturing enterprises, this paper brings out a kind of a collaborative product development service-on-demand mode based on web-service, and a framework for this service-on-demand mode are also given. According to these, this research sets up a web based collaborative product development service platform, analyzes the function structure, service flow and the main implement techniques. The service pattern and the platform have already applied to collaborative product development in small and medium manufacturing enterprises and have helped to increase technique innovation, reduce the total time and cost in development process.