Abstract: By combining Beidou satellite high precision positioning technology and real-time dynamic technology as well as dynamic coordinate system conversion technology, a high-precision positioning system of on-site staff in railway marshalling station was developed for supervision and safety protection of on-site staff. The system can realize real-time high precision positioning and activity tracking of the on-site staff and set up electronic fence in operating areas, which can help strengthen supervision over on-site staff and standardize the process of on-site operations, guaranteeing the safety of the on-site staff and improving the efficiency of operations.