The invention relates to a dirt-collecting device for a floor-cleaning machine, for picking up a liquid from a floor surface which is to be cleaned, having a carrier and at least one wiping member for wiping the floor surface, the carrier and the at least one wiping member bounding a suction channel which opens out into a suction mouth and of which the free cross-sectional area, through which a suction stream can pass, decreases, at least in one channel portion, in a direction away from the suction mouth. In order to produce such a dirt-collecting device in a more cost-effective manner, it is proposed according to the invention that the suction channel has disposed in it at least one channel-narrowing member, which is produced separately from the carrier. The invention also relates to a floor-cleaning machine having such a dirt-collecting device.