A method of controlling a laundry treatment apparatus including a drum configured to provide a space for receiving laundry, a duct installed outside of the drum and configured to guide air exhausted from the drum to the drum, an impeller disposed in the duct and configured to circulate air, a refrigerant tube configured to form a circulation path of refrigerant, an evaporator disposed in the duct and configured to allow heat exchange between the refrigerant and air introduced into the duct, a condenser disposed in the duct and configured to allow heat exchange between the refrigerant and air passing around the evaporator, a compressor configured to compress the refrigerant emerging from the evaporator and to supply the compressed refrigerant to the condenser, an expansion valve configured to adjust a pressure of the refrigerant transferred from the condenser to the evaporator through control of an opening degree thereof, and a temperature sensing unit configured to measure a temperature of the air exhausted from the drum, the method comprising: a course setting procedure comprising receiving, as an input, a first control command including: at least one of data for RPM control of the impeller, data for RPM control of the compressor or data for opening degree control of the expansion valve; a hot air supply procedure (S11, S13, S15) comprising supplying heated air to the drum using the impeller and the compressor; a temperature measurement procedure comprising measuring, by the temperature sensing unit, a temperature of the air exhausted from the drum and introduced into the duct during the hot air supply procedure; a first control procedure comprising operating the impeller, the compressor and the expansion valve in accordance with the first control command when the temperature measured by the temperature sensing unit is equal to, or higher than, a predetermined reference temperature; and a second control procedure comprising operating the impeller, the compressor and the expansion valve in accordance with a second control command different from the first control command when the temperature measured by the temperature sensing unit is lower than the predetermined reference temperature; characterised in that the said temperature measurement procedure is begun subsequent to the start of the hot air supply procedure (S11, S13, S15), and that the second control command comprises a variation of all of: the data for RPM control of the impeller, the data for RPM control of the compressor, and the data for opening degree control of the expansion valve received in the course setting procedure such that in the second control procedure the output of the heat pump and the output of the fan are maximized by increasing to a maximum value thereof all of: the RPM of the impeller, the RPM of the compressor and the opening degree of the expansion valve. a course setting procedure comprising receiving, as an input, a first control command including: at least one of data for RPM control of the impeller, data for RPM control of the compressor or data for opening degree control of the expansion valve; a hot air supply procedure (S11, S13, S15) comprising supplying heated air to the drum using the impeller and the compressor; a temperature measurement procedure comprising measuring, by the temperature sensing unit, a temperature of the air exhausted from the drum and introduced into the duct during the hot air supply procedure; a first control procedure comprising operating the impeller, the compressor and the expansion valve in accordance with the first control command when the temperature measured by the temperature sensing unit is equal to, or higher than, a predetermined reference temperature; and a second control procedure comprising operating the impeller, the compressor and the expansion valve in accordance with a second control command different from the first control command when the temperature measured by the temperature sensing unit is lower than the predetermined reference temperature; characterised in that the said temperature measurement procedure is begun subsequent to the start of the hot air supply procedure (S11, S13, S15), and that the second control command comprises a variation of all of: the data for RPM control of the impeller, the data for RPM control of the compressor, and the data for opening degree control of the expansion valve received in the course setting procedure such that in the second control procedure the output of the heat pump and the output of the fan are maximized by increasing to a maximum value thereof all of: the RPM of the impeller, the RPM of the compressor and the opening degree of the expansion valve.