As an important public transportation mode, the development of urban rail has given a new mission height based on smart urban rail, in the context of the dual carbon national strategy. This article first analyzes and summarizes the characteristics and connotations of smart urban rail and green urban rail, proposes key technologies for the integration of smart urban rail and green urban rail, and puts forward prospects from the aspects of green smart urban rail construction, energy transformation, multimodal transportation, and smart city integration, to promote the intelligent, green, and high-quality development of urban rail.