In recent years，with the scale expansion of EHV/UHV transmission lines，the accidents caused by lightning stroke are increasing． Lightning stroke performance analysis model based on multi － wave impedance of the tower is established，at the same time，lightning performance of winding analysis model is established which takes the action of ground inclination and grounding resistance into account． Aiming at the tower model in a running line，the influence rules of thunderstorm day， ground lightning density and grounding resistance on the tripping rate of counterattack are analyzed，and the influence rules of thunderstorm day，ground lightning density and ground inclination on shielding failure tripping rate are also analyzed． At last， after the surge arresters are installed，the back － flashover resistance level and the lightning shielding failure proof level of the circuit increase by 32． 5% and 162． 3% respectively，and the total tripping rate of the circuit decreases obviously．