To provide a chair having the function as an ordinary chair, an easy chair, and a bed, a simple structure, and easy operation.

This functional chair is composed of a combination of a seat back rocking means formed rockable by providing a lower part of a seat back installing frame 4 on a pivot shaft 3, a seat moving means formed rockable by providing a rocking shaft 7 near one end of a seat frame 6 provided with a seat body 27, a connecting shaft on the other end, the center of an arm 8 on both ends of the connecting shaft, one end of the arm 8 on the both outside lower ends of the seat back installing frame 4 so that the other end of the arm 8 is located on the lower side, and one end of a connecting arm 14 on both ends of the rocking shaft 7, and connecting the other end of the arm 8 and the center of the connecting arm 14 by a connecting rod 15, and a seat movement smoothing means formed by providing a guide plate 20 which is bored with a curved guide groove 19 on the opposite side end of the turning shaft 3 on both sides of a support stand 2, providing a guide shaft provided with a bearing in a lower part near the rocking shaft 7 of the seat frame 6, and correspondingly providing the bearing and the guide groove 19.