A discharging unit for discharging a printing medium from an image forming apparatus includes an elastic roller and a curl preventing roller to oppose each other in a pressing relationship forming a nip therebetween to reduce curling of a print medium passing through the nip. At least one of the elastic roller and the curl preventing roller is allowed to move towards or away from the other roller so that the nip can be adjusted to accommodate different thicknesses of varying types of printing medium.