With the development of power production technology, especially the comprehensive popularization of digital grid, people have higher and higher requirements for power equipment (such as transmission lines, substations, etc.), and traditional transmission line data acquisition methods can no longer meet the requirements for data accuracy and visualization. In this paper, three-dimensional modeling is carried out on the commonly used ultra-high voltage towers such as cat head towers and dry pyramids; on high and ultra-high voltage transmission lines, different shapes of power towers are used, and computer-aided design is used to design them as CSG (Constructive Solid Geometry) and embed it into CAD (Computer Aided Design) software, which can greatly improve the efficiency of 3D vector reconstruction of electric poles. In the 3D modeling of the transmission line, this paper extracts the information of the tower, improves the 3D model library of the tower, and displays it. In the geometric reconstruction results of the transmission line, the sag of line 1 is 33.9 m, the height of the transmission tower is 34.7 m, and the span length of the transmission line is 240.7 m. In-depth study of the multi-working condition geometric reconstruction mechanism of transmission lines is very important for enhancing the ability of the power grid to resist natural disasters and improving the safe operation level of the power grid.