Abstract: Site survey should be organized according to the task before the transmission line work. Aiming at solving the problems existing in traditional survey methods, a digital survey technology is proposed. Data acquisition is carried out by unmanned aerial vehicle (UVA) patrolling and light detection and ranging (LiDAR) scanning, and 3-dimension (3D) modelling of the tower and line ARE established after the calculation, feature extraction and classification of the acquired data. Meanwhile, 3D modeling can also be established based on tilted photography. The results show that the application of digital survey technology can achieve precise mastery of the state of overhaul equipment, site environment and operational needs, and identify possible safety risks at the site in advance.