To enhance efficiency in frame material working and an assembling work concerning a chair where a plurality of frame materials are connected to constitute leg frames.

Forelegs 4 and rear legs 5 crossing in a chevron shape are respectively connected by joints 6. Each joint 6 consists of a tubular part 6a to which the rear leg 5 is fitted from an inside and a boss part 6b to which the foreleg 4 is fitted from an outside. The forelegs 4 are horizontally deviated inward compared with the rear legs 5 in the front view of the chair. Thus the chair is horizontally stacked in a front and rear direction. Efficiency in a connection work is further improved in this structure than that of connection by welding. Besides, the upper end of the foreleg 4 is used in a flat state as it is so that time and labor are saved in machining the forelegs 4.