Abstract: A seat for a vehicle is provided with a sliding device including a slide-lock mechanism, the sliding device sliding a seat body in a case of releasing the slide-lock mechanism, a seatback including a reclining device, the seatback being tilted forward in a case of releasing the reclining device, a seat cushion including a tip-up device, the seat cushion being tipped up in a case of operating the tip-up device and a walk-in mechanism including a lever, the walk-in mechanism configured to release the slide-lock mechanism, release the reclining device and operate the tip-up device in proportion to a shifting length of the lever. The tip-up device is operated in a case where the lever is shifted in an intermediate position and the slide-lock mechanism and the reclining device are released in a case where the lever is shifted in an end position.