An air-conditioning apparatus comprising: an intermediate heat exchanger for heating and an intermediate heat exchanger for cooling by exchanging heat between a refrigerant and a heat medium different from said refrigerant a refrigeration cycle in which a compressor, an outdoor heat exchanger, at least one expansion valve, and a refrigerant-side channel of said intermediate heat exchanger (15a, 15b) are connected by pipelines through which said refrigerant flows; and a heat medium circulation circuit in which a heat medium-side channel of said intermediate heat exchanger (15a, 15b), a pump, and a use-side heat exchanger are connected by pipelines through which said heat medium flows, wherein said compressor and said outdoor heat exchanger are contained in an outdoor unit; said intermediate heat exchanger (15a, 15b) and said pump are contained in a relay unit; said use-side heat exchanger is contained in an indoor unit, respectively; and an expansion absorption device that absorbs volume change in both said heat medium heated and said heat medium cooled is connected to the suction side of said pump of said heat medium circulation circuit, characterized in that said relay unit is divided into a first relay unit and a second relay unit; a gas-liquid separator that separates the refrigerant into a gas and a liquid is contained in said first relay unit; said intermediate heat exchanger (15a, 15b) and said pump are contained in said second relay unit, respectively; said outdoor unit and said first relay unit are connected by two pipelines, which are inbound and outbound paths for the refrigerant, and said second relay unit and each of said indoor units are connected by two pipelines, which are inbound and outbound paths for the heat medium. a refrigeration cycle in which a compressor, an outdoor heat exchanger, at least one expansion valve, and a refrigerant-side channel of said intermediate heat exchanger (15a, 15b) are connected by pipelines through which said refrigerant flows; and a heat medium circulation circuit in which a heat medium-side channel of said intermediate heat exchanger (15a, 15b), a pump, and a use-side heat exchanger are connected by pipelines through which said heat medium flows, wherein said compressor and said outdoor heat exchanger are contained in an outdoor unit; said intermediate heat exchanger (15a, 15b) and said pump are contained in a relay unit; said use-side heat exchanger is contained in an indoor unit, respectively; and an expansion absorption device that absorbs volume change in both said heat medium heated and said heat medium cooled is connected to the suction side of said pump of said heat medium circulation circuit, characterized in that said relay unit is divided into a first relay unit and a second relay unit; a gas-liquid separator that separates the refrigerant into a gas and a liquid is contained in said first relay unit; said intermediate heat exchanger (15a, 15b) and said pump are contained in said second relay unit, respectively; said outdoor unit and said first relay unit are connected by two pipelines, which are inbound and outbound paths for the refrigerant, and said second relay unit and each of said indoor units are connected by two pipelines, which are inbound and outbound paths for the heat medium.