A laundry treating apparatus comprising: a dryer including: a first cabinet; and a first drum rotatably disposed in the first cabinet; a washing machine including: a second cabinet arranged vertically with respect to the first cabinet; a tub disposed in the second cabinet; and a second drum rotatably disposed in the tub; wherein the laundry treating apparatus comprises: a refresher including a third cabinet disposed at a lateral side of the first cabinet and the second cabinet, the refresher comprising an inner space for receiving laundry; a heating device disposed under the tub, the heating device configured to heat air supplied into the first drum and the inner space of the third cabinet, characterized by the heating device including a heat exchanger unit (52, 53); a drain pan for storing condensate, the drain pan disposed under the heat exchange unit (52, 53); and a drain pump configured to discharge water in the tub and the condensate in the drain pan, wherein the drain pump is disposed below the tub and in the heating device. a first cabinet; and a first drum rotatably disposed in the first cabinet; a washing machine including: a second cabinet arranged vertically with respect to the first cabinet; a tub disposed in the second cabinet; and a second drum rotatably disposed in the tub; wherein the laundry treating apparatus comprises: a refresher including a third cabinet disposed at a lateral side of the first cabinet and the second cabinet, the refresher comprising an inner space for receiving laundry; a heating device disposed under the tub, the heating device configured to heat air supplied into the first drum and the inner space of the third cabinet, characterized by the heating device including a heat exchanger unit (52, 53); a drain pan for storing condensate, the drain pan disposed under the heat exchange unit (52, 53); and a drain pump configured to discharge water in the tub and the condensate in the drain pan, wherein the drain pump is disposed below the tub and in the heating device. a second cabinet arranged vertically with respect to the first cabinet; a tub disposed in the second cabinet; and a second drum rotatably disposed in the tub; wherein the laundry treating apparatus comprises: a refresher including a third cabinet disposed at a lateral side of the first cabinet and the second cabinet, the refresher comprising an inner space for receiving laundry; a heating device disposed under the tub, the heating device configured to heat air supplied into the first drum and the inner space of the third cabinet, characterized by the heating device including a heat exchanger unit (52, 53); a drain pan for storing condensate, the drain pan disposed under the heat exchange unit (52, 53); and a drain pump configured to discharge water in the tub and the condensate in the drain pan, wherein the drain pump is disposed below the tub and in the heating device. a refresher including a third cabinet disposed at a lateral side of the first cabinet and the second cabinet, the refresher comprising an inner space for receiving laundry; a heating device disposed under the tub, the heating device configured to heat air supplied into the first drum and the inner space of the third cabinet, characterized by the heating device including a heat exchanger unit (52, 53); a drain pan for storing condensate, the drain pan disposed under the heat exchange unit (52, 53); and a drain pump configured to discharge water in the tub and the condensate in the drain pan, wherein the drain pump is disposed below the tub and in the heating device.