The invention relates to the lightning protection grounding field and particularly relates to a novel power transmission overhead ground wire lightning protection grounding method. Double overhead ground wires of a power transmission line comprise a first overhead ground wire and a second overhead ground wire, multiple poles are arranged on the power transmission line, according to the pole arrangement order, the double overhead ground wires realize transposition at even-number poles of the power transmission line, and the double overhead ground wires and odd-number poles are in direct grounding connection at the odd-number poles of the power transmission line. According to the method, a grounding mode of the overhead ground wires is changed, energy saving and consumption reduction of the overhead ground wires are facilitated, a grounding mode of even-number segment transposition and odd-number segment grounding is employed, circulation and damage are reduced, not only can a metal tool be prevented from heating, but also influence on a shunting coefficient of the ground wire is not great.