Abstract: With the continuous development of informationization, digitization, and intelligence in China's railways, as well as the continuous improvement of their technological level and service capabilities, railway enterprises are facing increasingly severe network security situations. This paper analyzed the current situation and challenges of railway network security, and studied defense measures for railway cyberspace security based on key elements such as information ledger, network traffic, data flow, and closed-loop processes. The aim is to further enhance the defense capabilities of railway cyberspace security and provide useful references for the formation of railway new productive force and digital transformation.