HOLDER AND WIRE HARNESS

A holder configured to be fitted to a tube that is made of metal and through which a wire is to be inserted, the holder including: a tubular main body that includes a first end and a second end opposite to the first end, and is configured to be inserted into the tube; and a cover formed protruding radially outward from an outer circumferential surface of the main body at the first end, wherein: the cover is formed only in a portion of the main body in a circumferential direction, and the cover includes a wall that protrudes radially outward from the outer circumferential surface of the main body, and a guard that extends from a radially outward end of the wall toward the second end of the main body.