The invention relates to an illumination device. The illumination device comprises a mounting seat, a telescopic connecting rod, a bearing seat and an illuminating lamp; the mounting seat is arrangedon a frame body, and the mounting seat is located on one side, away from a basket, of a backboard; one end of the telescopic connecting rod is connected to the mounting seat, and the other end of thetelescopic connecting rod extends to the position above a basketball court; the bearing seat is arranged on the frame body, one end, away from the frame body, of the bearing seat is connected to the telescopic connecting rod, and an interval is formed between the bearing seat and the mounting seat in the horizontal direction; the height of the mounting seat is smaller than that of the bearing seat; and the illuminating lamp is connected to one end, away from the mounting seat, of the telescopic connecting rod, and the light-emitting surface of the illuminating lamp is used for facing the ground of the court. According to the illuminating device, a player cannot be influenced by dazzling light rays when the player plays a ball game at night and looks at the backboard, and the height and theillumination range of the illuminating lamp can be adjusted.