A suction device according to the present invention has: an outer tube connected to a fluid supply unit on a base-end side thereof and including an opening edge section and a suction tube provided in the outer tube and connected to a negative pressure generating unit on a base-end side thereof, the suction tube including an opening edge section, wherein an annular fluid supply passage is formed between an inner peripheral surface of the outer tube and an outer peripheral surface of the suction tube, and the opening edge section of the suction tube is placed inside the opening edge section of the outer tube toward the base-end side thereof.
