Meteorological equipment installed in the field to transmission line to provide power for construction convenient transmission cables are used for overhead laying, the overhead cable easy induction lightning pulse, causing rear end equipment is damaged by the impact. In order to study the transmission lines of different laying ways have different lightning protection effect, through the establishment of the equivalent model of distributed capacitance and inductance characteristics analysis of transmission cable, and the cable laying method analysis different distribution parameters change caused by cable distribution parameters, the lightning pulse attenuation, the cable laying underground with lightning protection good effect on the system equipment. The engineering example shows that the effect of the half burying mode of the power supply cable is general, and the effect of the direct buried soil is the best, and the longer the length of the buried, the better the lightning protection effect.