In order to solve the problem that the peak sidelobe of the traditional time delay algorithm is relatively low when it faces impulse noise, and there are many false positives that are difficult to judge, a new weighted Gaussian correlation entropy time delay estimation method is proposed and applied to the simulation model of cable fault location. The simulation results show that, compared with the existing methods, it not only obtains a good time delay estimation effect in the impulsive noise environment, but also maintains a high positioning accuracy in the strong impulsive noise interference. In the background of pulse noise with different intensities, the calculation results show that compared with the other three methods, the absolute value of the main peak to side lobe ratio increases by more than 0. 020 3 dB, the ratio of misjudged peak to fault point peak decreases by more than 0. 053 9, and the mean square error decreases by more than 1. 863 6 m.