Lightning is an important factor affecting the safe and reliable operation of power transmission and distribution lines. As most power transmission and distribution lines are built in mountainous areas with complex terrain and changeable weather, the lightning accidents in mountainous areas are much higher than those in plain areas. Firstly, the mechanism of lightning damage and common measures of lightning protection are analyzed. Then, taking Lufeng line in Yunnan province as the object, taking the topographic and geomorphic characteristics of the line, the activity intensity of lightning strike and the line structure into consideration, three measures are compared by increasing the number of insulator string pieces, reducing the grounding resistance of poles and towers, and erecting lightning conductor across the line. Finally, erecting lightning conductor across the line is adopted to rectify the line. The feasibility and practicability of the rectification scheme are proved by calculation.