The invention relates to an automatic locating method and device for a discharge source. The device includes a signal receiving device, a processing device, a camera device and a rotation motor driving the camera device to rotate. The signal receiving device is used for receiving electromagnetic signals generated by the discharge source and recording electromagnetic wave signal waveform data. The processing device is used for reading the electromagnetic wave signal waveform data, calculating the arrival direction of the electromagnetic waves relative to the signal receiving device and controlling motor rotation according to the arrival direction. The camera device is used for shooting after rotating to a target position and obtaining pictures used for locating the discharge source. By adopting the method and device provided by the invention, convenience is made for workers to determine the location of the discharge source or power equipment with the discharge source directly and to find the aging parts of insulation material. Insulation failure and interference to the surrounding electromagnetic environment can be avoided. According to the invention, through program control of self-programmed software, the whole process can be implemented in a one-key manner. Therefore, a new method is provided for tour inspection of insulation failures of power transmission lines.