Abstract: The wide application of Building Information Modeling(BIM) can improve the technical level of railway engineering construction and the ability of information management. It is also the core and direction of railway engineering construction informatization, and has great development potential and application value for railway engineering construction. As the source of BIM life cycle, BIM design plays an important role in promoting BIM technology. Based on the design stage of railway engineering construction project, this paper studied the workflow and component reuse of BIM based collaborative design, proposed the collaborative design process under BIM and BIM component library scheme, which improved the efficiency and convenience of BIM modification and maintenance, implemented the sharing and utilization of design resources, and laid a foundation for the establishment of BIM design collaborative management and forward design system.