Provided is a wire harness having a shielding structure that can achieve a required shielding effect while sufficiently meeting the requirements of weight reduction and cost reduction. The wire harness includes a wire group constituted by a plurality of wires and a retaining member that surrounds the wire group such that the wire group is retained in the form of a bundle, wherein the wire group is configured to include a first wire composed of a linear conductor that is located toward the center of the wire group, a tube-shaped wire sheathing that surrounds the first wire, and a second wire and a third wire that are composed of an opposing pair of split tube-shaped conductors that are insulated from each other with the first wire and the wire sheathing being interposed therebetween.