Electrically foldable seat

A seat apparatus (1) comprising a seat back (2) as a backrest portion, a seat cushion (3) as a seating portion, a link mechanism (4) for supporting the seat cushion on a vehicle floor, and a driving source (61) for actuating the link mechanism (4) to position the seat cushion (3) between a seating position and a stored position, characterized in that the link mechanism (4) is pivotally mounted on the vehicle floor for defining a posture thereof.