In an air conditioner in which plural outdoor units are connected to plural indoor units, at least one outdoor unit is provided with a compressor having a power control mechanism for inhibiting a part of a compression work, and the power of the compressor is made variable by controlling the power control mechanism. The outdoor unit is provided with two heat exchangers which are designed in a substantially U-shaped form, and disposed in a main body of the outdoor unit so that the opening sides thereof are confronted to each other, and the refrigerating elements which constitutes a refrigerant circuit and contains at least the compressor, an accumulator, etc. are disposed in a space which is surrounded by the two heat exchangers.