A wire harness includes a tubular external member and one or a plurality of conduction paths inserted into the external member and protected by the external member. The external member includes at least one fixed form insertion part in which an inside width is wider than an outside width of the one or the plurality of conduction paths, and a plurality of narrow-width insertion parts which are elastically deformable and in which an inside width is narrower than the outside width of the one or the plurality of conduction paths. The plurality of narrow-width insertion parts are arranged along a tube axial direction alternately and integrally with the at least one fixed form insertion part.