Combined with the three dimensional model, virtual reality and network information, the CIM model is extend and defined on the basis of CIM transmission line model and the GIS technology. At the same time, the basic framework of 3D visualization platform of transmission line based on asset data model and spatial information model is proposed. Moreover, a method of coordinate transformation based on genetic algorithm is introduced to solve the problem of low accuracy of coordinate conversion in three-dimensional information grid platform. Accordingly, it is convenient for locating the position and direction of the tower and lines accurately. The validity and the correctness of the proposed method are verified through the experiment.