Abstract: In response to the national "dual carbon" policy and to enhance the greenization and intelligent level of urban rail transit, this paper designed a multimodal data integration and analysis system for urban rail transit carbon emissions, analyzed the characteristics of carbon emission data in urban rail transit, proposed a multimodal data integration system architecture, introduced key technologies such as carbon emission accounting based on operational boundaries, multimodal data analysis, and time series based model prediction and optimization. This system was based on the urban rail transit energy management platform, could calculate energy carbon emissions and optimize energy efficiency, help to improve the utilization efficiency of urban rail transit energy, implement high-quality and greenization development of urban rail transit.