The utility model discloses an insulator arcing fault positioning device based on discharging light detection. The insulator arcing fault positioning device comprises a micro-power-consumption pinhole camera, a storage battery pack, an image processing single-chip microcomputer, a wireless communication module and a receiving terminal. The micro-power-consumption pinhole camera is used for collecting insulator arcing discharging light in real time. The image processing single-chip microcomputer is used for controlling collection parameters of the micro-power-consumption pinhole camera, and determines whether arcing discharging happens to the insulator or not on the basis of a collection result. The wireless communication module is used for transmitting arcing fault information to the receiving terminal. The storage battery pack is used for supplying power to the micro-power-consumption pinhole camera, the image processing single-chip microcomputer and the wireless communication module. The receiving terminal is used for receiving and storing the arcing fault information transmitted by the wireless communication module, and giving warnings to work staffs. The insulator arcing fault positioning device can position an insulator with an arcing fault visually, accurately and highly efficiently, improve work efficiency of wire patrol personnel, and shorten time for fault elimination.