A dish washer includes a steam generating unit that is configured to control the amount of steam in accordance with the amount of items in the dish washer. The steam generating unit is positioned outside of the tub and is configured to generate and supply steam to the tub. The dishwasher includes a fluid supplying passage that supplies washing fluid to the steam generating unit. A steam discharging passage is configured to discharge steam that is generated from the steam generating unit to the tub.