An air-conditioning apparatus comprising: a refrigerant circuit configured by connecting, by pipes, a compressor that compresses a heat-source-side refrigerant, a refrigerant flow switching device (11, 28) for switching a circulation path for the heat-source-side refrigerant, a heat-source-side heat exchanger for causing the heat-source-side refrigerant to be subjected to heat exchange, an expansion device for adjusting a pressure of the heat-source-side refrigerant, and one or more intermediate heat exchangers that exchange heat between the heat-source-side refrigerant and a heat medium different from the heat-source-side refrigerant; a heat medium circuit configured by connecting, by pipes, one or more pumps for allowing the heat medium subjected to heat exchange by the intermediate heat exchangers to circulate, a use-side heat exchanger that exchanges heat between the heat medium and air in an air-conditioning target space, and a flow switching device (32, 33) that switches, for the use-side heat exchanger, between passage of the heated heat medium and passage of the cooled heat medium; a controller configured to perform, at a time when a heat recovery defrosting operation for causing the heat-source-side refrigerant that has been heated by the heat medium in the intermediate heat exchangers to flow into the heat-source-side heat exchanger and defrosting is performed, control such that the pumps are driven at a specific pump capacity or higher; and a refrigerant pressure sensor that detects a low-pressure-side pressure in the refrigerant circuit, characterized in that in the heat recovery defrosting operation, the controller determines whether or not the low-pressure-side pressure of the refrigerant circuit is equal to or greater than a specific pressure, and when it is determined that the low-pressure-side pressure of the refrigerant circuit has become lower than the specific pressure, the controller reduces a compressor capacity of the compressor and increases an evaporating temperature in the intermediate heat exchangers. a refrigerant circuit configured by connecting, by pipes, a compressor that compresses a heat-source-side refrigerant, a refrigerant flow switching device (11, 28) for switching a circulation path for the heat-source-side refrigerant, a heat-source-side heat exchanger for causing the heat-source-side refrigerant to be subjected to heat exchange, an expansion device for adjusting a pressure of the heat-source-side refrigerant, and one or more intermediate heat exchangers that exchange heat between the heat-source-side refrigerant and a heat medium different from the heat-source-side refrigerant; a heat medium circuit configured by connecting, by pipes, one or more pumps for allowing the heat medium subjected to heat exchange by the intermediate heat exchangers to circulate, a use-side heat exchanger that exchanges heat between the heat medium and air in an air-conditioning target space, and a flow switching device (32, 33) that switches, for the use-side heat exchanger, between passage of the heated heat medium and passage of the cooled heat medium; a controller configured to perform, at a time when a heat recovery defrosting operation for causing the heat-source-side refrigerant that has been heated by the heat medium in the intermediate heat exchangers to flow into the heat-source-side heat exchanger and defrosting is performed, control such that the pumps are driven at a specific pump capacity or higher; and a refrigerant pressure sensor that detects a low-pressure-side pressure in the refrigerant circuit, characterized in that in the heat recovery defrosting operation, the controller determines whether or not the low-pressure-side pressure of the refrigerant circuit is equal to or greater than a specific pressure, and when it is determined that the low-pressure-side pressure of the refrigerant circuit has become lower than the specific pressure, the controller reduces a compressor capacity of the compressor and increases an evaporating temperature in the intermediate heat exchangers. in the heat recovery defrosting operation, the controller determines whether or not the low-pressure-side pressure of the refrigerant circuit is equal to or greater than a specific pressure, and when it is determined that the low-pressure-side pressure of the refrigerant circuit has become lower than the specific pressure, the controller reduces a compressor capacity of the compressor and increases an evaporating temperature in the intermediate heat exchangers.