Provided is a curvature restricting member, allowing for a curvature of the wire harness in a predetermined allowable direction, and regulating the curvature of the wire harness in a regulating direction beyond a predetermined limit state or more, the curvature restricting member includes: a plurality of member pieces arranged along the wire harness; a flexible connecting portion connecting adjacent ones of the plurality of member pieces to each other, wherein the curvature is allowed in the allowable direction by adjacent ones among the plurality of member pieces at the curbed portions separating from each other on the side opposite to the connecting portion and the connection portion bending, and wherein the curvature is not allowed in the restricting direction beyond the limit state by adjacent ones among the plurality of member pieces at the curbed portion abutting against each other on the side opposite to the connecting portion.