With the progress of the social development of our country, the laying speed of the cable line is increasing. The cross-linked polyethylene cable is widely laid in the country by virtue of its excellent operating performance, but in a complex operating environment, the cable is often subjected to different degree of insulation aging. At present, in the field test and state detection of the high-voltage cross-link cable, there is no significant breakthrough in the partial discharge experiment under the voltage of the ringing wave, and the relevant experimental data is not available. In this paper, the principle of partial discharge experiment of oscillation wave and its experimental device are introduced, and the difference of three insulation aging degree is obvious through contrast analysis. The relative relationship between the insulation aging degree and the partial discharge parameters (discharge initial voltage, discharge electricity, etc.) of the cable is obtained. By means of partial discharge location, the location analysis of cable insulation aging fault is carried out, and the advantages and applicability of partial discharge experiment under damping oscillatory wave voltage are proved.