The car body is an important component of a sedan, serving as the carrier for all the vehicle's parts. Its weight and manufacturing costs account for approximately 40% to 60% of the total cost of the vehicle. It is typically composed of over 300 to 500 thin sheet stamping parts with complex spatial surfaces, which are assembled on the production line in large batches and at high speeds by up to 55 to 75 assembly stations. The number of clamping and positioning points can reach as many as 1700 to 2500, and the number of welding points can exceed 4000 to 5000. Therefore, there are numerous intermediate steps, which pose significant difficulties in the process design and planning of the white body as well as the production line. Currently, the overall layout and design of the white body's process still rely on manual experience-based design, and the design concepts and methods are quite outdated. This results in the need to spend a large amount of foreign exchange on the planning and design of the white body production line, relying on foreign expertise, which does not adapt to the development of China's automotive industry. Using the developed 'Body-in-White Process Planning and Design System', process planning and design work for the body-in-white can be completed on a computer, solving a series of problems such as the design of body-in-white welding processes, production process information management, and line planning. This minimizes the possibility of huge losses, and its economic benefits are immeasurable. The Body-in-White Process Planning and Design System is a complex and vast system that provides a complete collaborative working environment for manufacturing process design, planning, management, and optimization for the entire body-in-white manufacturing system. It involves factors such as people, computer hardware and software, production environment, etc., to achieve the management of the body-in-white manufacturing process.