This work presents an innovative model for 1 the derivation of permittivity evolution of polyethylene 2 (PE)-based materials with aging. First, the derivation of 3 the microscale contributions to the real permittivity of 4 methylene unit [constitutive repetitive unit (CRU) of PE] and 5 its oxidation products, that is, ketones and hydroperoxides, 6 in the solid state is presented. Then, a chemical kinetic 7 model is recalled predicting the concentration, under proper 8 hypotheses, of the oxidized species created during poly-9 mer aging. The proposed model combines the concentra-10 tions of methylene unit and its oxidation products with the 11 respective contribution to permittivity, providing the trend 12 of permittivity of polymer with aging. Results depict good 13 agreement with the experimental data, validating the model.