An apparatus for dropping paper sheets at a predetermined paper-stack position when the paper sheets are ejected from a facsimile device includes a conveyor belt which carries the paper sheets, a housing, containing the conveyer belt, which is detachably installed on the facsimile device where the paper sheets are ejected from the facsimile device such that the conveyor belt extends from a paper outlet of the facsimile device to the predetermined paper-stack position, and a driving motor, driving the conveyor belt to carry the paper sheets, which starts operating about a time when the facsimile device starts a paper-ejection operation thereof and stops operating about a time when the facsimile device stops the paper-ejection operation thereof.