Abstract: Urban rail transit project involves many professionals and complex models. In order to improve the efficiency and precision of modeling, the secondary development technology of Revit BIM(building information modelling) software platform and the C# programming language are used, to achieve the automatic establishment of the parametric family of line structures related to bridge, tunnel, track and rail by controlling the relevant parameters. According to the line laying ways, the whole line is divided into a plural sections, and Revit software secondary development technology is used for the section-level loading, thus the automatic assembly of BIM for all the structural components on urban rail transit line is realized. Finally, a rapid stitching method for threedimensional BIM model of urban rail transit is established, in order to reduce the complexity of model refinement and splicing.