The present invention relates to a dishwasher. The dishwasher of the present invention may include a sump for holding cleaning water, a cleaning pump for pumping the cleaning water from the sump, a spray arm for spraying the cleaning water through two or more nozzles, a supply flow passage for forming a flow passage to supply the cleaning water pumped by the cleaning pump to the spray arm, and an air mixing unit for drawing external air to spray the cleaning water through the nozzles together with the air. The air mixing unit may be mounted between the nozzle which sprays the cleaning water and an inlet of the supply flow passage connected to the spray arm, or the end of the supply flow passage connected to the spray arm. Accordingly, the washability of the dishwasher can be improved without increasing the amount of water used.