Abstract: In China, the total length of high-voltage transmission lines is more than 1 million kilometers, and the lines are dense and widely distributed. Most of the transmission lines of 10 kV and above pass through the forested areas in the mountains. At present, the traditional manual pruning method has been unable to meet the actual large-scale transmission and distribution line corridor pruning needs. In order to solve this “line-tree contradiction” and ensure the safe operation of power lines in transmission and distribution networks, pruning robots based on trees in transmission and distribution line corridors are constantly developed. Firstly, the key components of the pruning machine are introduced. Secondly the characteristics of four types of pruning robots are expounded according to the operation mode. The perception and control technology used by the pruning robot are introduced, including visual perception, tactile perception, motion path planning control, etc. Then, the functional characteristics of the existing pruning robots are compared. Finally, the existing problems and development trends of the pruning robots are prospected to provide reference for the application of related power technologies.