Abstract: A detachable swivel tin chair comprises a seat, chair leg and tray, the tray comprises an upper connecting tray, a lower connecting tray and a rotating device. The rotating device comprises a first connecting piece, a ball bearing and a second connecting piece. The first and second connecting piece rotate relative to each other through the ball bearing, the seat is fixedly connected to the upper end of the upper connecting tray. The chair legs include four supporting legs, the upper end of the legs are provided with an arc-shaped folded edge, which is provided with three first screw holes, the lower end of the lower connecting tray is provided with second screw holes. A long annular reinforcing rib is welded on the middle and lower sections of the supporting leg and connecting pieces are welded at the middle and lower sections on the inner side of the supporting feet.