An air-conditioning apparatus comprising: a refrigeration cycle that includes a compressor configured to compress a heat source side refrigerant, a refrigerant flow switching device configured to switch between paths for circulation of the heat source side refrigerant, a heat source side heat exchanger configured to allow the heat source side refrigerant to exchange heat, an expansion device configured to regulate a pressure of the heat source side refrigerant, and at least one intermediate heat exchanger configured to exchange heat between the heat source side refrigerant and a heat medium different from the heat source side refrigerant, the compressor, the refrigerant flow switching device, the heat source side heat exchanger, the expansion device, and the intermediate heat exchanger being connected by pipes; a heat medium circuit that includes at least one pump configured to circulate the heat medium related to heat exchange in the intermediate heat exchanger, a use side heat exchanger configured to exchange heat between the heat medium and air related to an air-conditioned space, and a flow switching valve configured to switch between a passage for the heated heat medium through the use side heat exchanger and a passage for the cooled heat medium therethrough, the pump, the use side heat exchanger, and the flow switching valve being connected by pipes; characterized by an outdoor air temperature detection device configured to detect the temperature of outdoor air; a controller configured to perform a freeze prevention control to prevent freezing of the heat medium in the heating medium circuit, wherein the controller, when determining during suspension of an air conditioning operation that the temperature detected by the outdoor air temperature detection device is at or below a first predetermined temperature and a first predetermined period of time has elapsed since the pump was stopped, perform control such that the pump is activated to circulate the heat medium through the heat medium circuit. a refrigeration cycle that includes a compressor configured to compress a heat source side refrigerant, a refrigerant flow switching device configured to switch between paths for circulation of the heat source side refrigerant, a heat source side heat exchanger configured to allow the heat source side refrigerant to exchange heat, an expansion device configured to regulate a pressure of the heat source side refrigerant, and at least one intermediate heat exchanger configured to exchange heat between the heat source side refrigerant and a heat medium different from the heat source side refrigerant, the compressor, the refrigerant flow switching device, the heat source side heat exchanger, the expansion device, and the intermediate heat exchanger being connected by pipes; a heat medium circuit that includes at least one pump configured to circulate the heat medium related to heat exchange in the intermediate heat exchanger, a use side heat exchanger configured to exchange heat between the heat medium and air related to an air-conditioned space, and a flow switching valve configured to switch between a passage for the heated heat medium through the use side heat exchanger and a passage for the cooled heat medium therethrough, the pump, the use side heat exchanger, and the flow switching valve being connected by pipes; characterized by an outdoor air temperature detection device configured to detect the temperature of outdoor air; a controller configured to perform a freeze prevention control to prevent freezing of the heat medium in the heating medium circuit, wherein the controller, when determining during suspension of an air conditioning operation that the temperature detected by the outdoor air temperature detection device is at or below a first predetermined temperature and a first predetermined period of time has elapsed since the pump was stopped, perform control such that the pump is activated to circulate the heat medium through the heat medium circuit.