A clothes dryer comprising: a drum configured to accommodate an object to be dried; a first sensor configured to sense a dry state of the object to be dried accommodated in the drum; a heating unit configured to heat air supplied into the drum; a blower comprising a fan (41, 81) configured to generate a flow of air passing through the inside of the drum; a second sensor configured to sense a temperature of the air discharged from the drum; and a processor configured to: control a rotation speed of the drum, control a temperature of the air discharged from the drum to control the internal temperature of the drum, and control a rotation speed of the fan (41, 81), wherein the clothes dryer performs sterilization courses comprising different courses, including: a first course in which the processor is configured to control the heating unit to discharge air from the drum at at least a first temperature, and control the blower to maintain the rotation speed of the fan (41, 81) at a first speed; a second course in which the processor is configured to control the heating unit to discharge air from the drum at at least a second temperature, and control the blower to maintain the rotation speed of the fan at a second speed; and a third course in which the processor is configured to control the heating unit to discharge air from the drum at at least a third temperature, and control the blower to maintain the rotation speed of the fan at a third speed, wherein when a sterilization course is started, the processor is configured to control the clothes dryer to either (i) perform the second course after performing the first course or (ii) perform the third course without performing the first course and the second course, based on the dry state of the object to be dried sensed by the first sensor, wherein the first speed is greater than the second speed and the third speed, and wherein the third temperature is higher than the first temperature and the second temperature. a drum configured to accommodate an object to be dried; a first sensor configured to sense a dry state of the object to be dried accommodated in the drum; a heating unit configured to heat air supplied into the drum; a blower comprising a fan (41, 81) configured to generate a flow of air passing through the inside of the drum; a second sensor configured to sense a temperature of the air discharged from the drum; and a processor configured to: control a rotation speed of the drum, control a temperature of the air discharged from the drum to control the internal temperature of the drum, and control a rotation speed of the fan (41, 81), control a rotation speed of the drum, control a temperature of the air discharged from the drum to control the internal temperature of the drum, and control a rotation speed of the fan (41, 81), wherein the clothes dryer performs sterilization courses comprising different courses, including: a first course in which the processor is configured to control the heating unit to discharge air from the drum at at least a first temperature, and control the blower to maintain the rotation speed of the fan (41, 81) at a first speed; a second course in which the processor is configured to control the heating unit to discharge air from the drum at at least a second temperature, and control the blower to maintain the rotation speed of the fan at a second speed; and a third course in which the processor is configured to control the heating unit to discharge air from the drum at at least a third temperature, and control the blower to maintain the rotation speed of the fan at a third speed, wherein when a sterilization course is started, the processor is configured to control the clothes dryer to either (i) perform the second course after performing the first course or (ii) perform the third course without performing the first course and the second course, based on the dry state of the object to be dried sensed by the first sensor, wherein the first speed is greater than the second speed and the third speed, and wherein the third temperature is higher than the first temperature and the second temperature. a first course in which the processor is configured to control the heating unit to discharge air from the drum at at least a first temperature, and control the blower to maintain the rotation speed of the fan (41, 81) at a first speed; a second course in which the processor is configured to control the heating unit to discharge air from the drum at at least a second temperature, and control the blower to maintain the rotation speed of the fan at a second speed; and a third course in which the processor is configured to control the heating unit to discharge air from the drum at at least a third temperature, and control the blower to maintain the rotation speed of the fan at a third speed, wherein when a sterilization course is started, the processor is configured to control the clothes dryer to either (i) perform the second course after performing the first course or (ii) perform the third course without performing the first course and the second course, based on the dry state of the object to be dried sensed by the first sensor, wherein the first speed is greater than the second speed and the third speed, and wherein the third temperature is higher than the first temperature and the second temperature.