A dishwasher is provided that may include a tub configured to define a washing space in which a washing object is washed, the tub having an open side, a first accommodating rack configured to accommodate the washing object inside of the tub, the first accommodating rack being unloadable from the tub, and a door configured to selectively open and close the open side of the tub, the door supporting the first accommodating rack when the first accommodating rack is unloaded. The tub may include a first protrusion protruding from an inner sidewall of the tub toward the washing space so as to support the first accommodating rack and guide movement of the first accommodating rack, and a second protrusion provided above the first protrusion and protruding from the inner sidewall of the tub toward the washing space so as to prevent the first accommodating rack from being lifted upward when the first accommodating rack is unloaded.