The cable accessory interface is a multilayer composite dielectric insulation structure, which is prone to partial discharge ( PD ) under physical conditions such as temperature, air pressure , and electric field. In order to study the evolution process of partial discharge under various stress conditions, a typical knife mark defect is designed in the 10kV cable terminal, and a collaborative aging platform under the multi-stress conditions of " cold and heat load-power frequency voltage-impulse voltage" is built in the laboratory. The platform is used to perform aging test on the cable, and the power frequency partial discharge test platform is used to detect the partial discharge of the cable terminal under different aging periods. The wave method is used to de-noise the partial discharge signals of the cable accessories under different aging stages, and the PD pulses in the partial discharge signals after the de-noising are extracted by the threshold window lift to construct the PRPD spectrum of the partial discharge signals of the cable accessories. The experimental results show that, under the condition of multiple stresses, under different aging degrees , the partial discharge of the knife mark defect cable accessory experiences three " ups and downs" breakdowns , and the discharge amplitude has a multi-stage " increase-decrease" variation trend.