The lift chair is a new type of chair, which mainly consists of seat plate, backrest, stent, stent rocker arm, lift positioning device and chair feet, characterized in that: between the stent and the chair feet by the stent rocker arm for the corresponding articulation, the stent rocker arm hinged in the chair feet hinged axis as the center of the circle for the up and down rotation, when rocking the stent rocker arm driven stent lifting and lowering, to achieve the lifting and lowering of the seat plate; In addition, between the stent and the chair feet are also set up to lift the positioning device. In addition, a lifting and positioning device is also provided between the bracket and the chair foot.