An engagement convex portion is formed in a grommet of a two-piece clip, and a head portion-side engagement concave portion is formed in a pin of the two-piece clip. When the pin is pushed into the grommet to a maximum push-in position, an inner end of the engagement convex portion of the grommet abuts against a middle of a tip-side concave portion wall surface of the head portion-side engagement concave portion. Thus, in the maximum push-in position, when a tip portion of the pin is pushed back in an extracting direction, the tip-side concave portion wall surface of the head portion-side engagement concave portion of the pin slides against the inner end of the engagement convex portion of the grommet.