In one embodiment, a supply mechanism is provided. The supply mechanism supplies accumulated paper sheets to a takeout position sequentially. A takeout belt having adsorption hole runs along a surface of the takeout position. An opening of a negative pressure chamber is arranged so as to face the takeout belt. A suction unit sucks air existing at the takeout position via the opening and the adsorption holes. The suction unit causes a negative pressure to act on each of the paper sheets so that each is adsorbed onto an adsorption surface of the takeout belt. The suction unit has an air supply port to supply air into the negative pressure chamber. The air supply port is arranged so that the air supplied via the air supply port is directed to a position and in a direction different from those of the opening.