An air-conditioning apparatus comprising: - a compressor to allow a refrigerant to be injected into a portion thereof located intermediate of a compression stroke, suck the refrigerant having a low pressure, compress the refrigerant, and discharge the refrigerant having a high temperature; - an indoor heat exchanger to exchange heat between air to be conditioned and the refrigerant; - a first flow rate control device to adjust and control a flow rate of the refrigerant passing through the indoor heat exchanger; - a plurality of outdoor heat exchangers connected in parallel to exchange heat between outdoor air and the refrigerant, - the compressor, the indoor heat exchanger, the first flow rate control device, and the plurality of outdoor heat exchangers being connected by pipes to form a main refrigerant circuit in which the refrigerant circulates; - a first defrosting pipe connected to the compressor and the plurality of the outdoor heat exchangers to allow a branched part of the refrigerant discharged from the compressor to pass therethrough and flow into at least one of the outdoor heat exchangers to be defrosted; - a first pressure adjustment device provided on the first defrosting pipe to adjust a pressure of the refrigerant passing through the first defrosting pipe to a medium pressure higher than the low pressure and lower than the high pressure; - a second defrosting pipe connected to the compressor and the plurality of the outdoor heat exchangers to allow the refrigerant that has passed through the at least one of the outdoor heat exchangers to be defrosted to pass therethrough to be injected into the compressor, characterized in that the air-conditioning apparatus further comprises a second pressure adjustment device provided on the second defrosting pipe to adjust a pressure of the refrigerant passing through the second defrosting pipe to an injection pressure. - a compressor to allow a refrigerant to be injected into a portion thereof located intermediate of a compression stroke, suck the refrigerant having a low pressure, compress the refrigerant, and discharge the refrigerant having a high temperature; - an indoor heat exchanger to exchange heat between air to be conditioned and the refrigerant; - a first flow rate control device to adjust and control a flow rate of the refrigerant passing through the indoor heat exchanger; - a plurality of outdoor heat exchangers connected in parallel to exchange heat between outdoor air and the refrigerant, - the compressor, the indoor heat exchanger, the first flow rate control device, and the plurality of outdoor heat exchangers being connected by pipes to form a main refrigerant circuit in which the refrigerant circulates; - a first defrosting pipe connected to the compressor and the plurality of the outdoor heat exchangers to allow a branched part of the refrigerant discharged from the compressor to pass therethrough and flow into at least one of the outdoor heat exchangers to be defrosted; - a first pressure adjustment device provided on the first defrosting pipe to adjust a pressure of the refrigerant passing through the first defrosting pipe to a medium pressure higher than the low pressure and lower than the high pressure; - a second defrosting pipe connected to the compressor and the plurality of the outdoor heat exchangers to allow the refrigerant that has passed through the at least one of the outdoor heat exchangers to be defrosted to pass therethrough to be injected into the compressor, a second pressure adjustment device provided on the second defrosting pipe to adjust a pressure of the refrigerant passing through the second defrosting pipe to an injection pressure.