There is provided a structure for mounting an attachment for vehicle capable of absorbing the marginal difference of a front spoiler and reducing the procedures for controlling the dimension of the front spoiler. The structure for mounting a front spoiler on a front bumper includes: a male clip provided on the front spoiler; an insertion hole provided on the front bumper for inserting the male clip therethrough; and a female clip engaged with the male clip and allowing the front spoiler to be held by the front bumper. The male clip is loosely inserted through the insertion hole and engaged with the female clip around the insertion hole via an abutting brim, thereby producing a gap between the insertion hole and the male clip, thus increasing the degree of freedom of positional adjustment, reducing the steps for mounting and controlling the accuracy of the attachment, reducing the overall cost.