A laundry treating apparatus comprising: a cabinet; a drum disposed inside the cabinet, wherein the drum has an inner space for receiving laundry therein; a duct system including an air discharge duct for discharging air inside the drum to an outside of the drum, an air supply duct for supplying air to the drum, and a connection duct for connecting the air discharge duct and the air supply duct to each other; a fan for moving air inside the drum along the duct system; a heat-exchanger including a heat-absorber disposed inside the connection duct to remove moisture from air, and a heat-emitter disposed inside the connection duct to heat air passing through the heat-absorber; a water collector for storing therein water removed from air passing through the heat-absorber; an water ejector disposed in the duct system and defining a water flow path for suppling water to the heat-absorber to remove foreign substances remaining on the heat-absorber; a water flow-path controller including a controller housing having an inner space for storing water therein, a water supply pipe for supplying water into the controller housing, a water discharge pipe for discharging water inside the controller housing, and a valve constructed to control opening and closing of the water discharge pipe; a pump including a pump housing having an inner space for storing water therein, a first connection pipe communicating with the water collector for guiding water inside the water collector to the pump housing, a second connection pipe communicating with the water ejector for guiding water inside the pump housing to the water ejector an impeller rotatably disposed inside the pump housing, and an impeller driver for rotating the impeller; and characterized in that the pump further comprises: a third connection pipe communicating with the water supply pipe for guiding water inside the pump housing to the water supply pipe, a discharge hole extending through a bottom face of the pump housing, wherein one end of the third connection pipe is connected to the discharge hole. a cabinet; a drum disposed inside the cabinet, wherein the drum has an inner space for receiving laundry therein; a duct system including an air discharge duct for discharging air inside the drum to an outside of the drum, an air supply duct for supplying air to the drum, and a connection duct for connecting the air discharge duct and the air supply duct to each other; a fan for moving air inside the drum along the duct system; a heat-exchanger including a heat-absorber disposed inside the connection duct to remove moisture from air, and a heat-emitter disposed inside the connection duct to heat air passing through the heat-absorber; a water collector for storing therein water removed from air passing through the heat-absorber; an water ejector disposed in the duct system and defining a water flow path for suppling water to the heat-absorber to remove foreign substances remaining on the heat-absorber; a water flow-path controller including a controller housing having an inner space for storing water therein, a water supply pipe for supplying water into the controller housing, a water discharge pipe for discharging water inside the controller housing, and a valve constructed to control opening and closing of the water discharge pipe; a pump including a pump housing having an inner space for storing water therein, a first connection pipe communicating with the water collector for guiding water inside the water collector to the pump housing, a second connection pipe communicating with the water ejector for guiding water inside the pump housing to the water ejector an impeller rotatably disposed inside the pump housing, and an impeller driver for rotating the impeller; and characterized in that the pump further comprises: a third connection pipe communicating with the water supply pipe for guiding water inside the pump housing to the water supply pipe, a discharge hole extending through a bottom face of the pump housing, wherein one end of the third connection pipe is connected to the discharge hole.