A curvature regulating member and a power supply device to which the curvature regulating member is applied are provided. The curvature regulating member has a plurality of member pieces arranged along a wire harness, and a flexible connection. The curvature regulating member regulates a curvature of the wire harness on a predetermined plane by contact with the adjacent member pieces. A burr (strip projection) is provided in an inner surface of the receiving groove of the wire harness in at least one of the member pieces. Further, a recessed portion is provided in an area of the inner surface including the burr (strip projection).