An embodiment relates to a dish washer. A dish washer according to an embodiment comprises: a tub that defines a space for washing dishes; a water supply unit that has a water chamber where water supplied from the outside collects, to wash the dishes; a sump that is supplied with water from the water chamber and supplies wash water into the tub; and a heat exchange passage through which the wash water in the sump flows and exchanges heat with the water in the water chamber while flowing.