The present disclosure provides a method of controlling a laundry treating apparatus including a tub in which a drum accommodating clothing is rotatably disposed, a heat exchanger configured to perform heat exchange between air discharged from the tub and a refrigerant in a circulation flow path through which the air circulates, a filter configured to filter the air, a first cleaning mechanism configured to apply cleaning water to any one of the filter and the heat exchanger, and a second cleaning mechanism configured to apply the cleaning water to the other of the filter and the heat exchanger. The method includes measuring a flow rate while supplying water into the tub, and controlling, based on the flow rate, a first flow path control valve for regulating water supply to the first cleaning mechanism and a second flow path control valve for regulating water supply to the second cleaning mechanism.