The present invention relates to a clothes treating apparatus comprising: a housing; a tub which is provided in the housing and stores water; a drum which is provided in the tub and stores laundry; a driving unit which is provided on the external bottom surface of the tub and rotates the drum; a heater which heats the water stored in the tub; and a receiving part which is downwardly recessed from the bottom surface of the tub so that the heater is received therein, and which has one portion thereof protruding from the outer circumference to the radial direction of the bottom surface of the tub.