Abstract: The current network environment is becoming more and more complex, and network security is the basis of railway security. It is of great practical significance to carry out research on railway security protection against complex network environment. According to the characteristics and requirements of railway network security, this paper took network security data as the core, established a 4-layer railway network security protection architecture, and combined with the technologies of authentication centric security verification and computing power distribution for data computing and processing, implemented the whole process protection of railway network from data collection to safety analysis. This research can provide a reference for the implementation of railway network security defense.