When installing the cable terminal accessory, the sharp tool makes the main insulation leave scratches and is more likely to cause dis-charge, which poses a hidden danger to the safe operation of the power grid. In this paper, partial discharge tests were carried out on 10 cm, 10 mm, 30 mm, 50 mm and 70 mm XLPE cables with slitting scratches at 10 kV. Extract the discharge pulse waveform and analyze the discharge pulse of each defective cable, and analyze the falling time of the positive and negative pulse waveforms Tr+, Tr-, rise time Tf+, Tf-, width Tw+, Tw-, duration Tl, peak absolute value p, etc. Quantity and its difference. In addition, the normalization study of each pulse power spectrum was studied. The results show that as the scratch is away from the cut-off layer, the discharge pulse of the posi-tive half cycle shifts to the right and the pulse distance from the negative half cycle decreases; Tr-, Tf+, Tw+, Tl and p can better reflect the scratch position and discharge degree; as the distance between the scratch and the cut-off layer increases, the shape of the discharge pulse power spectrum evolves from "upper narrow and lower" to "narrower ics based on the characteristic parameters of the pulse can provide a basis for identifying the location and severity of the scratch.