A first crossmember is divided into a right crossmember and a left crossmember. A right fastened portion of a towing hook is inserted into the right crossmember, and a bolt is fastened by being passed through a bolt insertion hole of the right crossmember and a bolt insertion hole of the right fastened portion of the towing hook. A left fastened portion of the towing hook is inserted into the left crossmember, and a bolt is fastened by being passed through a bolt insertion hole of the left crossmember and a bolt insertion hole of the left fastened portion of the towing hook. Hereby, the attachment strength of the towing hook can be secured sufficiently, and even in a case where an input at the time of towing of a vehicle is excessive, the towing can be performed successfully.