A laundry treating machine comprising: an air supply unit for supplying air; a tub for having the air supplied thereto from the air supply unit to treat the laundry, the tub having an air recovery opening formed in an outside circumferential surface thereof for recovery of the air to the air supply unit and an inside circumferential surface used as a condensing surface for condensing moisture contained in the air; wherein the air supply unit is positioned on an upper side of the tub for supplying the air to a front of the tub, and circulating the air through the air recovery opening, and wherein the air supply unit includes: a fan positioned on an upper side of the air recovery opening for moving the air, a heating duct for heating the air being moved by the fan, and an air discharge hole for supplying the air heated at the heating duct to the front of the tub; a lint filter mounted to an inside of the air recovery opening for filtering the lint from the air; a filter cleaning unit for spraying cleaning water to separate the lint from the lint filter, characterized in that, the cleaning water sprayed from the filter cleaning unit is used as cooling water for cooling down the condensing surface of the tub; and a flow passage member (200, 300) is used for guiding the cleaning water dropping from the lint filter to an inside surface of the tub. an air supply unit for supplying air; a tub for having the air supplied thereto from the air supply unit to treat the laundry, the tub having an air recovery opening formed in an outside circumferential surface thereof for recovery of the air to the air supply unit and an inside circumferential surface used as a condensing surface for condensing moisture contained in the air; wherein the air supply unit is positioned on an upper side of the tub for supplying the air to a front of the tub, and circulating the air through the air recovery opening, and wherein the air supply unit includes: a fan positioned on an upper side of the air recovery opening for moving the air, a heating duct for heating the air being moved by the fan, and an air discharge hole for supplying the air heated at the heating duct to the front of the tub; a lint filter mounted to an inside of the air recovery opening for filtering the lint from the air; a filter cleaning unit for spraying cleaning water to separate the lint from the lint filter, characterized in that, the cleaning water sprayed from the filter cleaning unit is used as cooling water for cooling down the condensing surface of the tub; and a flow passage member (200, 300) is used for guiding the cleaning water dropping from the lint filter to an inside surface of the tub. a fan positioned on an upper side of the air recovery opening for moving the air, a heating duct for heating the air being moved by the fan, and an air discharge hole for supplying the air heated at the heating duct to the front of the tub; a lint filter mounted to an inside of the air recovery opening for filtering the lint from the air; a filter cleaning unit for spraying cleaning water to separate the lint from the lint filter, characterized in that, the cleaning water sprayed from the filter cleaning unit is used as cooling water for cooling down the condensing surface of the tub; and a flow passage member (200, 300) is used for guiding the cleaning water dropping from the lint filter to an inside surface of the tub.