PURPOSE: To improve resistance to lightening, to simplify manufacturing, to decrease manufacturing cost and to make weight light, in an overhead earth-wire by attaching conductive guard wire with a predetermined winding radio around the body of the overhead earth-wire.

CONSTITUTION: An inner layer of an overhead earth-wire 1 is a GS wire, and aluminum stranded wire 2 is positioned as an outer layer around the inner layer. A guard wire 3, made of aluminum, etc., is wound around the overhead earth-wire 1. The guard wire 3 is wound in the opposite direction to the strand direction of the aluminum stranded wire 2, which is on the outer layer of the overhead earth-wire 1. The guard wire 3 is wound around the overhead earth- wire 1, without any overlapping. At this time, when the width of the guard wire 3 is W, and distance between the guard wires 3 is S, winding ratio S/W of the guard wire 3 is made 2.0 or less. As the guard wire 3 is wound, this guard wire 3 is fused first at the time of lightening, so that fused damage does not occur on the overhead earth-wire 1 which consists of the aluminum stranded wire 2 and the GS wire.