The 3D model design of overhead transmission lines is the basis for the simulation and construction of transmission lines. The paper first introduces the composition of transmission lines, including various sub-models such as grounding lines, insulating blocks and poles, and then designs for actual engineering cases. Research, using the intelligent aerial survey system for aviation acquisition, establishing the dom and dem data of the transmission line corridor, and using the bim technology to model the transmission line to form a complete three-dimensional model.Finally, the research results are compared with the measured results. The research shows that the three-dimensional design of the transmission line is conducive to the path optimization and engineering measurement is faster and more accurate, and has certain application value.