An insulator fault locating system includes a cross arm and insulators below the cross arm. The outside of an insulator umbrella column is insulated, and a conductor bar is arranged in the hollow inside. The insulator fault locating system further includes a locating device and a remote monitoring center. The locating device includes a main control circuit, a signal trigger circuit, a wireless communication module and an alarm circuit. The input end of the signal trigger circuit is connected with the conductor bar, and the output end is connected with the main control circuit. The main controlcircuit is connected with the wireless communication module and the alarm circuit. The remote monitoring center is connected with a wireless module in the locating device through a wireless network.The fault of an insulator can be located without the need for workers to patrol the site or take photos.