WIRE HARNESS UNIT

A wire harness unit including: a plurality of conductive paths for conducting electricity between in-vehicle devices; and a cooling tube through which a coolant is able to flow for cooling the plurality of conductive paths, wherein: the plurality of conductive paths include a first conductive path and a second conductive path parallel to the first conductive path, the first conductive path includes a first inner insulating layer that is hollow and tubular, and a first tubular conductor that covers an outer circumferential surface of the first inner insulating layer, and the second conductive path includes a second inner insulating layer that is hollow and tubular, and a second tubular conductor that covers an outer circumferential surface of the second inner insulating layer.