The present invention discloses a BIM modeling and design method for elevated structures, including the following steps: S1, generating a spatial three-dimensional line based on the extracted line plane and longitudinal section data; S2, extracting the location of the center point of the pier plane and its corresponding substructure type, generating the initial model of each member of the corresponding pier substructure, and then generating the 3D model of the substructure; S3, extracting the upper standard structure contour parameters corresponding to the mileage point of each line S3, extract the upper standard structure profile parameters corresponding to each line mileage point, generate the final upper structure profile of each line mileage point, and then generate the upper structure 3D model based on the spatial 3D line sweep sampling; S4, generate a complete BIM model of the elevated structure. The present invention realizes three-dimensional visualization of the design of the elevated structure, and the generated model image is intuitive and easy to modify. In addition, the present invention establishes a full life cycle database of the elevated structure, which can provide more basis for later operation and maintenance.