The present invention discloses a Wheelchair with a Movable Seat. The device adds new designs of elevation mechanism and sliding rail mechanism, and makes design changes of chair frame and seat. The seat is mounted on the top of the elevation mechanism to be adjusted the height. By releasing the seat from the elevation mechanism, it can be moved between the wheelchair and a hospital bed or a car chair by the sliding rail mechanism. Whereby, the caretaker can move the patient in more convenient and safe way by the present invention.