The utility model discloses a ground down lead of an iron tower. The ground down lead of the iron tower comprises two round bars. The lower parts of the two round bars are welded together; the upper parts of the two round bars are separated to form a U shape; and a connecting plate is welded at the inner side of the upper part of each round bar and extends out of the corresponding round bar. By adopting the technical scheme, the two round bars with the connecting plates are adopted by the ground down lead, an angle iron plate of the iron tower is arranged between the two connecting plates, the two connecting plates are fixedly arranged on the angle iron plate through a galvanized bolt, and the lower parts of the round bars are connected with a ground grid, thus, the contact area between the angle iron plate of the iron tower and the ground down lead is increased by at least one time compared with original contact area, the condition that ground resistance is high due to the small contact area is well improved, and a powerful guarantee is provided for lightning protection of a circuit.