An actuator structure includes two half cylinders made respectively from the same mold and the two half cylinders engaged with each other to form an actuator. The actuator has an air reservoir chamber and a vane chamber dividing by a dividing unit, and the vane chamber has a vane inside. An O-shaped ring is formed around the vane and an elastic stopping edge is formed protrudingly from the O-shaped ring and linearly contacted an inner surface of the actuator. The volume ratio of the air reservoir chamber and the vane chamber is about three to one, and a channel groove is formed at an interface of the two half cylinders to connect an air inlet hole and a left side and a right side wall of the actuator. A fail-safe or dual-movement control structure is formed to control the direction of air supply to drive the shaft to rotate toward a predetermined direction, or utilizing the compressed air in the air reservoir chamber to force the vane to restore to its original position.