To provide an air conditioner which is constituted in such a way that its heat source equipment using a natural refrigerant which does not disrupt the environment is set up outdoors are its indoor machine which can be used safely is set up in a living space.

This air conditioner is provided with an air compressor 2, and a cooling apparatus 3 using a natural refrigerant and connected to an indoor machine 4 through a low-pressure air pipeline 5 and a high-pressure air pipeline 6. The air conditioner produces high-pressure cooling air by compressing the outside air by means of an outdoor air compressor 2, and cooling the compressed air by means of a cooling apparatus 3. The conditioner sends the high- pressure cooling air together with low-pressure cooling air induced from return air in a room or outside air by using part of the high-pressure cooling air as an induction pressure by means of a regulating valve 10. The high-pressure cooling air is blown out from an inductive outlet 12 and further reduced in temperature by reduced pressure expansion and, at the same time, induces the low-pressure cooling air and the air in the room. As a result, air-conditioning air, namely, cold air which is a mixture of the high-pressure cooling air and low-pressure cooling air is blown into the room.