The invention provides a device and a method used for preventing a grounding lead from burning. The device comprises an insulation shell, several resistors located in the insulation shell and a conducting ring. The inner side of each conducting ring is connected to one elastic touch finger so as to drive a conducting rod and make the elastic touch finger be contacted with the conducting rod. An incoming line terminal electrode, an outgoing line terminal electrode, the resistors, the conducting ring, the elastic touch finger and the conducting rod are connected so as to form a live-line loop and adjust a resistance value between the incoming line terminal electrode and the outgoing line terminal electrode. By using the device and the method, an induced current flowing through a grounding line is restrained, the grounding line and an electric wire are effectively protected from being damaged, grounding reliability is increased and work dangerousness is reduced. Simultaneously, a person does not need to check on the site after the grounding line is hitched and before the grounding line is dismounted next time so that manpower cost is saved.