Disclosed herein is air conditioner inspection method that is capable of reducing inspection time and increasing inspection efficiency. The air conditioner inspection method is applied to an air conditioner including a plurality of indoor units having cooling and heating valves and a plurality of mode change units connected to the indoor units, via pipes, to control refrigerant flow to the indoorunits such that cooling operation mode and heating operation mode of the respective indoor units are controlled. The air conditioner inspection method comprises operating all the indoor units in one of the cooling operation mode and heating operation mode for a predetermined period of time and, if all the indoor units are normally operated in the selected operation mode, determining that all the valves corresponding to the selected operation mode among the cooling and heating valves of the indoor units are normally operated.