A clip for use in a cushion for a seat is disclosed. The cushion includes a cushioned pad and a trim cover covering the cushioned pad, the cushioned pad having a recess portion and a wire embedded in the cushioned pad so as to be partially exposed to the recess portion from the cushioned pad, the trim cover having a portion, a longitudinal tensioning cord attached to the portion of the trim cover, a longitudinal bulged member provided along a longitudinal edge portion of the cord, and a laterally elongated through-hole formed in the cord. The clip comprises a frame body having a substantially U-shape in cross-section, the frame body including first and second spaced apart side portions and an intermediate portion interconnecting the side portions, a pair of spaced apart inverted-pawls provided at edges of both ends of the frame body so as to inwardly face each other, a hook portion provided on an outer surface of the intermediate portion, and a stopper piece provided on the first side portion of the frame body so as to stand up from the first side portion and extend beyond a space between the pawls toward the second side portion. The clip is adapted to be hooked between the bulged member and an exposed axial portion of the wire with the frame body receiving the bulged member therein and retainingly holding the bulged member, with the pawls being stoppingly engaged with the bulged member, with the stopper piece being inserted through the through-hole, and with the hook portion being hooked to the exposed axial portion of the wire, whereby the trim cover is tensioned and attached at the portion thereof to the cushioned pad by the clip. A vehicle seat wherein the trim cover is tensioned and attached at the portion thereof to the cushioned pad by a plurality of the clips is also disclosed.