a cabinet;

a drum disposed rotatably inside the cabinet and configured to accommodate laundry therein;

a fluid circulator configured to repeat endothermic and exothermic processes as fluid circulates therethrough;

an air circulator including (i) a fan configured to cause air heated through the fluid circulator to flow into the drum and (ii) a humidity sensor configured to measure a humidity of the air passing through the drum;

a driver including (i) a first driver configured to rotate the drum and (ii) a second driver configured to rotate the fan; and

a controller configured to perform a drying operation of the laundry by independently controlling the fluid circulator, the first driver, and the second driver,

wherein the drying operation includes (i) an efficiency increasing process for increasing drying efficiency inside the drum, (ii) an efficiency maintaining process for maintaining the drying efficiency, and (iii) an efficiency decreasing process for reducing the drying efficiency, and

wherein the controller is configured to determine to perform each of the efficiency increasing process, the efficiency maintaining process, and the efficiency decreasing process based on a measured value of the humidity sensor.