A seat (1) comprises: a seat member (3(2)) that includes a cushioning material (4); and a fastening member (5) that allows a trim cover (7) to be detachably attached to a predetermined position on the seat member (3). The fastening member (5) is constituted by a slide fastener that includes: a fastener part (51) constituted by one fastener half (511) and another fastener half (512); and a slider part. At least part of a base part (6) provided in the one fastener half (511) is embedded in the cushioning material (4), and part of the other fastener half (512) is fixed to the trim cover (7).