Abstract: In response to the problems of low system integration capability, inadequate data sharing, and weak intelligent application capability in the current railway office system, this paper focused on the goal of improving railway office efficiency and intelligence level in the context of digital and intelligent transformation. The paper designed and developed a railway digital office system, and elaborated on its architecture and functional modules in detail. It deeply integrated artificial intelligence technologies such as intelligent writing, intelligent process approval, audio and video processing, and natural language processing in key business scenarios such as document processing, supervision and urging, government duty, and conference management, and implemented intelligent reconstruction of business processes. The pilot application results in a certain railway unit show that the system can improve the efficiency of document drafting by over 50% compared with the traditional manual mode, reduce the error rate by 70%, shorten the document approval time from 2.5 days to 8 hours, and greatly optimize the efficiency of meeting organization and management. This system provides a feasible technical approach and practical reference for the railway industry to realize modernized management and efficient operation.