Abstract: In recent years, the lightning disasters occur frequently and the uncertainty of lightning brought more and more challenges to transmission line lightning protection and disaster mitigation work.Based on the characteristics of the lightning obey the extreme value distribution, In this study, use an overhead transmission line lightning strike probability prediction method base on the Generalized Pareto Distribution (GPD).According to the statistics in month, Using the method of average overrun function and probability weighted moment estimation method of GPD estimate the parameters of the model.Establishing regional GPD model of ground lightning density proposed the overhead transmission line lightning probability prediction method in extreme weather conditions.The analysis results base on the compare with the actual lightning trip-out rate show that: the proposed method can be well fitted lightning distribution, evaluation level of risk of transmission lines, provide support for transmission line lightning protection and disaster mitigation.