The lightning arrester insulator is a two-in-one product with a new composite structure, adopting a design philosophy of first blocking and then clearing. It enhances the insulation performance and anti-fouling level, suitable for insulating supports of overhead lines. It also has protective functions against lightning strikes that could break overhead insulated conductors, shatter porcelain insulators, and reduce lightning-induced tripping. The principle is: when the lightning overvoltage exceeds a certain value of the insulation blockage, a flashover discharge is induced between the arc rod and steel foot of the lightning arrester column, forming a short-circuit path. The subsequent power frequency arc then burns at the discharge gap to protect the conductor from burning. When used with insulated wires, this product also features a piercing power transmission function, making installation and construction extremely convenient and reliable. It avoids wire core waterlogging and corrosion by not needing to strip the insulation layer, and also reduces the labor intensity for operators. By integrating the column insulator and arc prevention hardware into one (at the same potential), it is unaffected by the supply side of the ring network (away from the power source), which further simplifies and beautifies the line while reducing costs.