Cooperative work is becoming a comprehensive and effective product design method, and the application of multimedia and multiple design modes has made cooperative design system more natural and easier to use. By now, most of the cooperative design is specific-task oriented and carried out through a specific multimedia cooperative design tool. But with the improved requirements of agility and design efficiency of product design, more and more attention is paid to the design platform that supports multiple design tasks using multiple cooperative design tools. Based on the analysis of a comprehensive cooperative design model, this paper presents a framework supporting multimedia and multiple design modes. This framework is based on an open hierarchy, which is able to embed multiple cooperative design tools. And it also provides a series of cooperative design services. Then several key technologies of the framework are discussed: the intelligent agent based cooperative tool configuration technique, synchronous/asynchronous design mode control, consistency control of the cooperative design object, and at last the extensible multimedia organization model. Finally, this paper will present an application example of the framework, and then will evaluate the framework and draw a conclusion.