In this paper, the ZnO surge arrester performance of power distribution class has been studied under different manufacturing conditions such as housing materials(polymeric, porcelain), interface sealants and one-body molding type. In the recent years, the polymeric ZnO surge arresters have been developed and put into operations based on their excellent characteristics. For polymeric surge arresters, the inner gas volume is extremely small, especially in solid insulation polymeric arresters there are not any gas volume inside arresters in the structure due to polymeric materials are filled into the internal gas volume. The sealing integrity is related to safe operation of surge arrester, the prime failure reason of porcelain housed arresters is moisture ingress. In this paper, the sealing integrity of polymeric surge arresters is investigated with moisture multi-aging test and ingress test. The evaluation techniques are used to inspect the sealing integrity of polymeric arresters, including leakage current, surface temperature, reference voltage and dissipation factor.