A refrigeration cycle apparatus comprising: a refrigeration cycle circuit including a plurality of load-side heat exchangers (7A, 7B, 7C, 7D, 7E, 7F); a plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) accommodating the plurality of load-side heat exchangers (7A, 7B, 7C, 7D, 7E, 7F); and a controller configured to control the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), each of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) including an air-sending fan (9A, 9B, 9C, 9D, 9E, 9F), at least one of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) including a refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F), characterized in that the controller is configured such that when refrigerant is detected by the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) included in any one of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), the controller causes the air-sending fans (9A, 9B, 9C, 9D, 9E, 9F) included in all of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) to operate, wherein the controller includes a plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F) configured to control the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), wherein at least one of the plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F) includes a control substrate (41A, 41B, 41C, 41D, 41E, 41F) to which the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) is non-detachably connected and a nonvolatile memory that is provided on the control substrate (41A, 41B, 41C, 41D, 41E, 41F), wherein the nonvolatile memory includes a leakage history memory region configured to store one of first information indicating that there is no refrigerant leakage history and second information indicating that there is a refrigerant leakage history, wherein the information stored in the leakage history memory region is changeable only in one direction from the first information to the second information, and wherein the controller is configured such that when refrigerant is detected by the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) included in at least one of the plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F), the controller is configured to change the information stored in the leakage history memory region of the indoor unit control unit (31A, 31B, 31C, 31D, 31E, 31F) detecting the refrigerant from the first information to the second information. a refrigeration cycle circuit including a plurality of load-side heat exchangers (7A, 7B, 7C, 7D, 7E, 7F); a plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) accommodating the plurality of load-side heat exchangers (7A, 7B, 7C, 7D, 7E, 7F); and a controller configured to control the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), each of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) including an air-sending fan (9A, 9B, 9C, 9D, 9E, 9F), at least one of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) including a refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F), characterized in that the controller is configured such that when refrigerant is detected by the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) included in any one of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), the controller causes the air-sending fans (9A, 9B, 9C, 9D, 9E, 9F) included in all of the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F) to operate, wherein the controller includes a plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F) configured to control the plurality of indoor units (1A, 1B, 1C, 1D, 1E, 1F), wherein at least one of the plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F) includes a control substrate (41A, 41B, 41C, 41D, 41E, 41F) to which the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) is non-detachably connected and a nonvolatile memory that is provided on the control substrate (41A, 41B, 41C, 41D, 41E, 41F), wherein the nonvolatile memory includes a leakage history memory region configured to store one of first information indicating that there is no refrigerant leakage history and second information indicating that there is a refrigerant leakage history, wherein the information stored in the leakage history memory region is changeable only in one direction from the first information to the second information, and wherein the controller is configured such that when refrigerant is detected by the refrigerant detection unit (99A, 99B, 99C, 99D, 99E, 99F) included in at least one of the plurality of indoor unit control units (31A, 31B, 31C, 31D, 31E, 31F), the controller is configured to change the information stored in the leakage history memory region of the indoor unit control unit (31A, 31B, 31C, 31D, 31E, 31F) detecting the refrigerant from the first information to the second information.