A dryer is provided. The dryer may include a main body having an inner space formed therein, a support body arranged in the main body so as to form a frame of the main body, a flexible drum rotatably installed on the support body so as to have a non-circular cross-section as it is rotated, and rotation guides arranged between the support body and the flexible drum so as to guide rotation of the flexible drum. A distance from a center of rotation of an inscribed circle contacting the inner circumferential surface of the flexible drum to one random point on the inner circumferential surface of the flexible drum is greater than a distance from the center of rotation of the inscribed circle to another point on the inscribed circle such that the drum maintains a non-circular cross section.