Disclosed is an air conditioner. The air conditioner includes: an indoor unit and an outdoor unit that circulates a refrigerant between the indoor unit and the outdoor unit, in which the outdoor unit includes a heat exchanger that exchanges heat with the refrigerant and a housing that houses the heat exchanger, the housing includes a first plate that is provided to surround the heat exchanger, and a second plate that is provided to cover an opening formed on an edge of the first plate, has a ventilation hole through which air is circulated between inside and outside of the housing, is made of a material having greater corrosion resistance than that of the first plate, and includes a screw coupling part provided to be coupled to the first plate.