To provide a detachable towing hook mounting structure to/from a bumper reinforcement so that the predetermined towing load can be received, and the original shock-absorbing function of the bumper reinforcement that the bumper reinforcement is squeezed in a collision is not impaired.

A towing hook mounting bracket 20 is inserted from an opening 21 of a front wall 14A of a bumper reinforcement 14 before a flange part 20-2 is abutted on a facing side, a flanged bolt 22 is inserted from a back side of the bumper reinforcement 14 through an opening 23 of a rear wall 14B of the bumper reinforcement, and the flanged bolt 22 is screwed to a screw hole 20B of the towing hook mounting bracket 20. The towing hook mounting bracket 20 is fastened only to the bumper reinforcement from the outside between the flange part 20-2 and a flange part 22-1 of the flanged bolt 22.