The invention discloses a high voltage line short circuit sensor comprising a current transformer connected with a cable, a signal processing circuit connected with the current transformer and used for controlling a lighting device to illuminate according to a signal outputted by the current transformer, and a fiber arranged on the lighting device and used for sending the lighting device optical signal to a host. The high voltage line short circuit sensor can timely determine whether the cable has faults or not, so workers can fast determine the line fault section according to the local alarm conditions, and fast find out the fault points; in addition, the fiber can transmit the collected signals, thus realizing optoelectronic isolations, and effectively solving insulation problems; energy loss is small in a signal transmission process; the high voltage line short circuit sensor is not affected by outer environment, and suitable for high voltage lines.