An air-conditioning apparatus, comprising: an intermediate heat exchanger that is configured to exchange heat between a refrigerant and a different heat medium from said refrigerant such as water and brine; a refrigeration cycle that is configured to connect a compressor, a heat source side heat exchanger, at least one expansion valve, and a refrigerant side flow path of said intermediate heat exchanger via piping through which said refrigerant flows; and a heat medium circulation circuit that is configured to connect a heat medium side flow path of said intermediate heat exchanger, a pump, and a use side heat exchanger via piping through which said heat medium flows, a temperature sensor (31, 32, 33, 34) that is configured to detect a temperature of said heat medium, installed in said heat medium circulation circuit, wherein said heat source side heat exchanger, said intermediate heat exchanger, and said use side heat exchanger are formed in separate bodies respectively, and, a controller that is configured to perform anti-freezing operation of said heat medium in an anti-freezing operation mode when a detection temperature of said temperature sensor becomes equal to or lower than a set temperature while said compressor or said pump is stopped, and wherein as said intermediate heat exchanger, an intermediate heat exchanger (15a or 15b) that is configured to heat said heat medium and an intermediate heat exchanger (15b or 15a) that is configured to cool said heat medium are provided, flow path switching valves (22, 23) that are configured to switch the flow path to each intermediate heat exchanger (15a or 15b) at the inlet side and outlet side of a heat medium side flow path of said use side heat exchanger are provided, and wherein said controller is further configured to, in said anti-freezing operation mode for said heat medium, control said flow path switching valves (22, 23) such that the heat medium from both the flow path connected with one of said intermediate heat exchangers (15a or 15b) and the flow path connected with the other intermediate heat exchanger (15b or 15a) is mixed by said flow path switching valves (22, 23), and part of the mixed heat medium circulates in said heat medium circulation circuit corresponding to said temperature sensor (31, 32, 33, 34) that detected a temperature equal to or lower than said set temperature. an intermediate heat exchanger that is configured to exchange heat between a refrigerant and a different heat medium from said refrigerant such as water and brine; a refrigeration cycle that is configured to connect a compressor, a heat source side heat exchanger, at least one expansion valve, and a refrigerant side flow path of said intermediate heat exchanger via piping through which said refrigerant flows; and a heat medium circulation circuit that is configured to connect a heat medium side flow path of said intermediate heat exchanger, a pump, and a use side heat exchanger via piping through which said heat medium flows, a temperature sensor (31, 32, 33, 34) that is configured to detect a temperature of said heat medium, installed in said heat medium circulation circuit, wherein said heat source side heat exchanger, said intermediate heat exchanger, and said use side heat exchanger are formed in separate bodies respectively, and, a controller that is configured to perform anti-freezing operation of said heat medium in an anti-freezing operation mode when a detection temperature of said temperature sensor becomes equal to or lower than a set temperature while said compressor or said pump is stopped, and wherein as said intermediate heat exchanger, an intermediate heat exchanger (15a or 15b) that is configured to heat said heat medium and an intermediate heat exchanger (15b or 15a) that is configured to cool said heat medium are provided, flow path switching valves (22, 23) that are configured to switch the flow path to each intermediate heat exchanger (15a or 15b) at the inlet side and outlet side of a heat medium side flow path of said use side heat exchanger are provided, and wherein said controller is further configured to, in said anti-freezing operation mode for said heat medium, control said flow path switching valves (22, 23) such that the heat medium from both the flow path connected with one of said intermediate heat exchangers (15a or 15b) and the flow path connected with the other intermediate heat exchanger (15b or 15a) is mixed by said flow path switching valves (22, 23), and part of the mixed heat medium circulates in said heat medium circulation circuit corresponding to said temperature sensor (31, 32, 33, 34) that detected a temperature equal to or lower than said set temperature.