The distribution parameters in the cable partial discharge propagation model are subject to change due to the aging of the cable. In this study, we firstly build a two-dimensional model of the cable in COMSOL Multiphysics based on the actual cable parameters, which are used to calculate the primary distribution parameters of the cable, and secondly build a partial discharge signal propagation circuit using Simulink for relevant simulations and calculations. The results show that the propagation characteristics of the partial discharge signal in the cable under different aging states are different, the attenuation of the signal amplitude becomes larger and the time to peak is delayed continuously as the aging time increases. Therefore, the study of the effects of cable aging on the parameters of the partial discharge propagation model has important reference significance for the localization technology of partial discharge in cables.