An electric component box that accommodates therein an electric component, which includes: a control board that controls an air conditioner indoor unit; a power supply and indoor-outdoor wiring terminal block that is provided on the control board and is connected to a communication wire wired from the air conditioner indoor unit to an air conditioner outdoor unit and is connected to a power wire that supplies power; and a communication-wire terminal block that is provided on the control board and is connected to a communication wire for an external input.