Abstract: Studying the full-wave electromagnetic transient characteristics of a transmission line during a lightning strike can obtain the probability of a flashover in the transmission line during a lightning strike,avoid damages to the lighteningstruck transmission line,and improving its safety and stability.In this paper,a lightning strike simulation model is constructed for transmission lines including towers,lightning currents,and transmission line models to simulate lightning strikes on transmission lines and analyze two types of voltages generated by lightning strikes on transmission lines: direct lightning overvoltage and induced overvoltage. This is based on the analysis of the full-wave electromagnetic transient characteristics of transmission lines under lightning strikes. The result shows that when the upper phase of the middle tower is hit by a lightning of 60 kA current,the base tower and adjacent towers of the conductor phase are prone to flashover within 1s of lightning. When the insulator is struck by lightning,an arc current of 500～600 k A is generated,causing damages to the insulator. Installing the lightning arrester in the conductor of the transmission line can avoid the tripping phenomenon when lightning strikes the transmission line.