Abstract: The domestic substitution of railway information system software and hardware is a necessary condition for maintaining information security and ensuring railway data privacy. This paper took the Office Automation(OA) system of China Railway Zhengzhou Group Co. Ltd. as the pilot of domestic substitution, studied the migration scheme of domestic substitution, and analyzed the current situation and demand of domestic substitution of OA system of China Railway Zhengzhou Group Co. Ltd., gave the technical route, data migration scheme and implementation process of domestic substitution, expounded the overall architecture and technical architecture of the localized smart OA system, which lays the foundation for the domestic substitution of railway core information system in the next step.