Abstract: A chair, with an elastic movable means capable of allowing the back of the chair to be leaned back at an angle of inclination, is disclosed. The chair has one or more leg frames. A seat frame is mounted to the top portion of the leg frames and holds a seat. A back frame is connected to the seat frame and holds a back. The elastic movable means is provided at the junction between the seat and back frames and allows the back frame to be elastically leaned back relative to the seat frame. The elastic movable means has two leaning angle limit units at both ends and one torsion bar extending between the two limit units. Each of the two limit units is fitted into the seat and back frames at opposite ends and limits the leaning angle of the back frame. The torsion bar elastically returns the back frame from a leaned position to the original position.