Take “Research on minitype universal autonomous docking mechanism” as an example, the paper studied on the platform of complex product’s cooperative design and simulation of mechanical field. The process of mechanical component design was introduced. The paper put forward the bottleneck problem in the design process of data transmission and gave the solution. A new method that uses HLA/RTI (High Level Architecture/Runtime Infrastructure) for function module communication was given. By using component technology and integrating all the function module of current commercial software based on the design process, this platform expands easily and the simulation sub-system can plug and play.