In this paper,a train reconnection scheme is designed based on RS485 communication mode.Compared with the WTB communication mode,RS485 has lower requirements for the transmission medium.It can realize long-distance data transmission without shielding lines by optimizing the communication rate.In this paper,the design logic of RS485 reconnection software is em-phatically described.Through loading verification,the vehicle reconnection data exchange,train grouping dynamic identification,and automatic function switching are realized.