Product design is crucial to improving product quality and lowering manufacturing costs. Cloud manufacturing is emerging as a new manufacturing model and an integrated technology and has become an important development direction for advanced manufacturing. To adapt to the transformation of traditional manufacturing to service-oriented and innovative manufacturing, this study investigates the current status of collaborative design and summarizes the problems regarding the sharing and on-demand use of massive resources in traditional manufacturing. It also proposes the architecture of a product collaborative design platform based on cloud manufacturing and explains the meaning of each layer in detail. Then three key technologies for building the platform are discussed: cloud manufacturing technology, product family and product platform technology, and product collaborative design technology. Finally, using a cloud-manufacturing-based product collaborative design platform system established by a company as an example, the system architecture and functions of the platform are analyzed, and the differences in task assign and completion time between cloud manufacturing and traditional manufacturing are compared. The effectiveness and superiority of the cloud manufacturing-based system are verified, and the application and research direction of the system are prospected.