An image forming apparatus including: a plurality of medium trays to stack a print medium having an image formed thereon by an image forming unit; a driving source to momentarily apply a direction switching signal; a selector to select a carrying path of the print medium having the image formed thereon, the carrying path directing the print medium to one of the plurality of medium trays; and a switch unit connected to the driving source to set a position of the selector in order to direct the print medium along the carrying path according to the direction switching signal. Accordingly, power is only used momentarily to direct the print medium to a medium tray from among a plurality of medium trays.