This paper introduction the impact of wildfire on power transmission lines and the status of research on monitoring wildfire around power transmission line, aiming at the present shortcomings of monitoring wildfire around power transmission line, we put forward the proposal of using Lidar to monitor wildfire around power transmission line This article starts from the principle of Lidar monitoring, which not only analyzes the certain limited validity of Lidar system monitors transmission line fires, but also proves that the Lidar system can be used for monitoring power transmission lines fires through the simulation experiment. Furthermore, according to the characteristic of Lidar system’s dead zone, we derive the optimal installation position for Lidar to monitor wildfire around power transmission line on theory.