An air conditioner is provided that may include a main body having an air inlet and an air outlet defined therein; a filter received in the main body to filter air suctioned into the main body; a heat exchanger configured to perform a heat exchange between a refrigerant and the air suctioned into the main body; and an ultraviolet (UV) sterilization module configured to sterilize the air suctioned into the main body. The UV sterilization module may include a porous main body in a mesh form, and a plurality of UV lamps. The porous main body may include a bent portion to allow the porous main body to conform to a shape of the heat exchanger. The main body may include a chassis, and a front frame at a front of the chassis. An inner space may be defined between the chassis and the front frame. The porous main body may be coupled to at least one of the chassis or the front frame, and the plurality of UV lamps may be arranged to be spaced from each other between the air inlet and the heat exchanger.