To enable the easy and exact mounting of a block-detecting sensor to a bumper of an automobile at a specified mounting angle.

A mounting structure for the block-detecting sensor 1 is configured such that: a body part 13 of the block-detecting sensor 1 is fitted into a mounting hole 7 from the external side face of a bumper fascia 5; a clip 19 having an elastic part 21 at the body part 13 of the sensor 1 is latched; and the block-detecting sensor 1 is fixed to the bumper fascia 5 by making the elastic part 21 of the clip 19 elastically contact with the internal surface of the bumper fascia 5. The mounting structure is also characterized in that the clip 19 comprises a fitting latching part 41 latched to the side of the body part 13 of the sensor 1, and the elastic part 21 is protruded in a state of at least a pair of loops from the fitting latching part 41 to make a loop tip side 45 of the elastic part 21 elastically contact with the internal surface of the bumper fascia 5.