The utility model relates to a cable monitoring system, and belongs to the electric power field. The system comprises a sensing unit group, a processor for receiving the parameter data of the sensing unit group, and a remote monitoring terminal for receiving signal data sent by the processor. Alarming signal is given off upon discovery of abnormal data when the genetic optimized vector machine method is employed to determine the normality of data. The cable monitoring system monitors cable on a real-time basis in multidirectional way, and monitors the temperature parameters of cable joints to prevent fire hazard due to high temperature caused by damaged joints. The external operation state of a cable can be obtained by monitoring the cable conductor, and the cable fault can be discovered timely, thereby reducing the false alarm caused by error number, and minimizing the influence of possible failure on the cable.