A display device of a dryer, which can achieve the reliability of a function to display a clogging degree in the dryer, is disclosed. The display device includes a display unit for displaying a clogging degree of an air passage through at least one level indicator, and a controller for controlling the display unit when power is supplied, such that the level indicator flickers for a predetermined time, and then displays the clogging degree of the air passage. The display for the clogging degree of the air passage is executed, following the display of a normal operation state of the display unit.