A dishwasher includes a main body having an open front, a washer tub being extracted from and retracted into the main body through the open front, the washer tub having an open top, a lid for closing the open top of the washer tub when the washer tub is fully retracted to be accommodated in the main body, and an extension member extending backward from a top rear portion of the washer tub. When the washer tub is fully extracted from the main body, a rear end of an inner wall of the washer tub is located in front of a front end of the main body and a free end of the extension member is placed under the lid.