The invention relates to a cable fault transient state travelling wave signal identification method and device. The method comprises acquiring and displaying output signals of transient state travelling waves; performing spectral analysis on pulse signals to obtain frequency domain signals; performing band-pass filtering on the frequency domain signals to obtain band-pass frequency domain signals; performing time domain analysis on the band-pass frequency domain signals to obtain time domain signals, and acquiring target signals in the time domain signals; according to the characteristics of standard discharge signals, determining whether the target signals are transient state travelling wave signals when cable faults occur. The cable fault transient state travelling wave signal identification method primarily separates the target signals and interference signals of the pulse signals according to the phase correlation of pulse signals and sinusoidal signals in power cable output signals, and compares the characteristics of the target signals and the standard discharge signals to determine whether the target signals are the transient state travelling wave signals when the cable faults occur, thereby avoiding mistaking the interference signals for the transient state travelling wave signals when the cable faults occur, and further improving the fault positioning accuracy.