Abstract: Through the research on the key technologies of modeling the maintenance data for important parts and components of locomotive, the unified management of standardization, format and modeling of the maintenance record data for important parts of locomotive was realized.This paper collected the data of the maintenance record sheet of each maintenance unit, combined the requirements of the maintenance procedures of parts and components, referenced the maintenance process of various parts and components, made the maintenance record sheet data modeling according to the types of parts and components, and then analyzed and processed the data, implemented the standardization and modeling application of the maintenance data for important parts and components of locomotive. It simplifies the collection mode of maintenance data, reduces the difficulty degree of using maintenance data, facilitates the maintenance of locomotive maintenance record data, and provides a good foundation for locomotive data-based maintenance.