Cross-Linked Polyethylene (XLPE) power cables are widely used for electric power distribution and transmission networks. They are suffering from long-term degradation under continuous electrical stress. During cable aging degradation, the surrounding electrical stress injects electronic charges in the insulation medium which influences the dielectric parameters of the material and can also cause irreversible damage to the power cable. This paper proposes a detailed simulation scheme for a 24kV power cable, which gives full consideration to the aging phenomenon based on COMSOL Multiphysics software. The impact of electrical stress in the insulation medium through the measurement of electric polarization in the insulation region is evaluated. The computational modeling and simulation of cable aging used is examined in a detailed manner. The dielectric parameters of the power cable under different operating voltages and the subsequent changes in the cable insulation material due to aging process are analyzed and studied. The obtained results show the relationship between dielectric polarization in the insulation medium and the operational voltage range. The results of the study could be utilized to evaluate the status of XLPE cable insulation to ensure that high quality of electric power is supplied to consumers and determine the possibility of an insulation breakdown under its operation.