The present disclosure relates to a laundry dryer control method comprising: a sterilizing and drying step of increasing the internal temperature of a cabinet for sterilization; a steam-washing step of supplying steam into a drum, in order to sterilize the drum, after the sterilizing and drying step; and a blowing step of circulating the air inside the drum after the steam-washing step, and thus the temperature of the drum is controlled so as to be greater than or equal to a reference temperature at which sterilization is performed so that the drum is sterilized.