For the reason that the rail flash welding equipment’s distribution scattered in remote locations,equipment management is usually inconvenient especially in case of the equipment failures where the fault is hardly to be handled onsite. Therefore,based on the UN5-150 ZB1 welding machine’s rail flash quality online monitoring and management system,design a remote monitoring management system and remote fault diagnosis system for rail scene flash welding. After comparison of the B/S and the C/S network communication structure,the system adopts the C/S structure for its suitability to the rail scene flash welding. The entire system consists of three subsystems:on-site monitoring computer,central server computer and GPRS network. The on-site monitoring computer is responsible for field data collection and responding to the center server to control the PLC. The center server receives,processes and stores various kinds of information sent from the on-site monitoring computer,besides,it sends related commands and monitors diagnoses to the on-site welding machine. The constructed system can realize the centralized management of multiple rail flash welding machine information in different geographical locations,and make full use of the resources of experts and scholars in remote places to remotely diagnose the faults occurred in the spot welder in time.