Abstract: Multiple lightning strikes will accelerate the aging rate of a zinc oxide arrester, reduce its service life and electrical performance, and even directly cause breakage and damage to it. In order to study the dielectric properties and the variation of internal microscopic parameters of the zinc oxide arrester after subjected to multiple lightning strikes, the multiple lightning strike experiment was carried out and its impact aging characteristics were studied. Firstly, the double- impact experiment on the zinc oxide arrester was carried out, and the DC voltammetric characteristic curves and the frequency domain dielectric spectroscopy data of the arrester were measured under different impact times. Secondly, the change of barrier height and depletion layer width of the zinc oxide grain boundary with the number of impacts was studied by using the current-temperature characteristics of the arrester. Finally, the parameters in the equivalent circuit of the arrester based on the extended Debye model (EDM) were identified and analyzed by using the grey wolf optimization algorithm. The results show that the barrier height of the zinc oxide grain boundary decreases with the increase of the impact times in both the low temperature area and the high temperature area, but the barrier height decreases faster in the high temperature area. There is a negative correlation between the barrier width and the impact times, and the barrier width in the low field strength area is larger than that in the high field strength area. In the EDM, the insulation resistance R₀, the geometric branch time constant τ₀ and the first polarized branch time constant τ₁ decrease with the increase of the impact times, and the third polarized branch capacitance C₃ increases with the increase of the impact times. The research results can provide a basis for the judgment of impact aging of zinc oxide arresters.