A seat apparatus for a vehicle includes: an unlocking lever that is operated so as to unfix a seat from a vehicle floor; and a control switch that is operated in order for the seat to switch between a deployed state in which the seat is supported on the vehicle floor and a folded state in which the seat is retracted in a concave retraction portion of the vehicle floor, when a support member of the seat is driven via the driving of an actuator, wherein the unlocking lever is provided in a back surface of a seatback which is disposed at an opening end of the concave retraction portion when the seatback is folded forward and the seat is retracted, and the control switch is provided integrally with the unlocking lever.