A wire harness including: an electric wire that includes a core wire and a covering material that covers the core wire; a connector that is attached to an end of the electric wire; and a seal that is interposed between the electric wire and the connector, wherein: the covering material includes a thin portion, which is thinner than other portions of the covering material, at a portion overlapping the seal in a radial direction, the covering material includes a distal-end non-thin portion and a proximal-end non-thin portion on two sides of the thin portion in a longitudinal direction, a first annular stepped surface is formed between the thin portion and the distal-end non-thin portion, and a second annular stepped surface is formed between the thin portion and the proximal-end non-thin portion.