A wire harness includes a cable, a connector including an outer housing including a resin, a cable insertion hole into which an end portion of the cable is inserted, and a concave portion formed on an insertion side of the cable insertion hole, and a welding member including a resin to provide air-tightness between the outer housing and the cable by being welded to the outer housing by ultrasonic welding. The welding member is formed around the cable so as to surround the cable while allowing a gap portion to have a predetermined clearance from the cable, and fitted into the concave portion of the outer housing. Melted resin of the welding member is to flow into the gap portion to form an airtight seal about the cable.