Abstract: Provided are a device and a method for live detecting a partial discharge of an overhead line in a distribution network and equipment along the line, including: acquiring a second synchronous pulse signal and a first partial discharge signal via a master detection unit; acquiring a first synchronous pulse signal and a second partial discharge signal via a slave detection unit; analyzing the second synchronous pulse signal and the first synchronous pulse signal via a main control computer to obtain time data; and calculating a propagation time based on the time data, synchronously processing the time data based on the propagation time to obtain reference zeros, and calculating a partial discharge location according to the first partial discharge signal and the second partial discharge signal based on the reference zeros.