In view of the ice melting of the ground wire of the deactivated line of a ±500 kV double-circuit DC transmission line with the same tower, when the ground wire of the deactivated line is melted under the condition of "one shutdown and the other operating", the failure of the ice melting device and the breakdown of the automatic wiring device and the lightning arrester caused by excessive induced voltage are studied. According to the calculation and analysis of 6 working conditions, the overvoltage level induced on the shutdown line when the corona initiation voltage of the live running circuit conductor is calculated, and the overvoltage suppression level and line energy are comprehensively considered, and the overvoltage suppression measures with 5 kΩ grounding high resistance are proposed, which can realize the induction voltage of more than 100 kV to less than 20 kV, and the effectiveness is verified by the actual line ice melting operation.