WIRE HARNESS

A wire harness, including: a first wire including a first core wire and a second wire including a second core wire, the first core wire and the second core wire being joined together, wherein the first core wire includes a first flat surface extending along an entire length of the first core wire in a length direction, the second core wire includes a second flat surface extending along an entire length of the second core wire in a length direction, and the first flat surface and the second flat surface are overlapped and joined.