Abstract: In response to the practical needs of localized replacement and seamless upgrade of the databases for the railway electronic payment platform, this study establishes a quantitative evaluation index system for domestic database adaptability based on the core characteristics and potential risk assessment of the databases of the railway payment platform. By relying on a domestic database test environment that simulates the actual production environment of the railway electronic payment platform, adaptability testing and comparative selection research are carried out on three candidate domestic database products, providing a reliable decision-making basis for scientific selection of domestic database alternatives. Finally, a targeted implementation path and risk management mechanism for domestic database adaptation of the railway electronic payment platform are proposed, so as to ensure the effectiveness of the domestic database adaptation transformation and the continuous and stable operation of services during the adaption period. The research results can provide practical and feasible references for the adaptation and selection of domestic databases in the same type of high-concurrency and high-availability key information systems.