Abstract: The present invention provides a microwave oven with a drainage system. It comprises a chamber, a slip groove disposed on the bottom side of the chamber, a drain hole unit disposed in the slip groove, a rotary pan, a bracket unit provided with rolling wheel unit which can slip along the slip groove. The rolling wheel unit on the bracket unit can bring water to the drain hole unit, so that the water in the chamber flows out of the chamber soon in order to ensure that no water remains in the chamber to achieve a better cooking effect and facilitate operation of the microwave oven.