Disclosed herein is a drying unit for washing machines that is capable of fully drying the wet laundry using hot wind. A condensing duct and a drying duct are connected to a tub to circulate air in the tub. Between the drying duct and the condensing duct is disposed a drying fan. To the condensing duct is attached air cooling device for condensing air in the condensing duct by means of cool air. In the drying duct is mounted a drying heater for heating air in the drying duct to change the air into hot wind. During the drying operation of the washing machine, the air passing through the condensing duct is condensed by air, which is an unlimited resource. Consequently, consumption of energy and resources is minimized during the drying operation of the washing machine.