Abstract: The research on the decomposition structure of EMU is one of the basic works of standardization and standardization of all kinds of technical information in EMU. Based on the analysis of the actual operation maintenance, such as China multiple platform vehicle mixed running, the depth study of EN15380 and other relevant standards, this article proposed the overall data architecture solution which was to give priority to function module decomposition structure, establish the mapping relation of the component decomposition structure of each vehicle platform. It has certain reference value for the construction of operation maintenance information system of EMU.