An air conditioning system, comprising: - three or more air conditioner bodies (12A, 12B, 12C) that perform air-conditioning operation; - three or more remote controllers (14A, 14B, 14C) that operate each of the air conditioner bodies; and - a pairing-setting unit (24A, 24B, 24C) that pairs each of the plurality of air conditioner bodies and each of the remote controllers (14A, 14B, 14C), wherein - the pairing-setting unit (24A, 24B, 24C) has a main machine registration function that registers a pair of the air conditioner body and the remote controller (14A, 14B, 14C), out of the conditioner bodies (12A, 12B, 12C) and the remote controllers (14A, 14B, 14C), as a main machine, and a sub machine registration function that registers the air conditioner body, which is registered as a main machine out of the air conditioner bodies, and a remote controller (14A, 14B, 14C) which is not registered as the main machine, as a sub machine, - a mode of operating the air conditioner body that is the main machine with the remote controller (14A, 14B, 14C) after registration of the main machine and the sub machine by the pairing-setting unit (24A, 24B, 24C) is defined as a main-machine operation mode, while a mode of operating the air conditioner body that is the sub machine with the remote controller (14A, 14B, 14C) is defined as a sub-machine operation mode, and characterized in that when the main-machine operation mode is shifted to the sub-machine operation mode, the remote controller (14A, 14B, 14C) receives operation information transmitted from at least two of the air conditioner bodies registered as the sub machine so as to acquire the operation information of at least two of the air conditioner bodies registered as the sub machine, and displays the acquired operation information on a display unit (34A, 34B, 34C) of the remote controller (14A, 14B, 14C). - three or more air conditioner bodies (12A, 12B, 12C) that perform air-conditioning operation; - three or more remote controllers (14A, 14B, 14C) that operate each of the air conditioner bodies; and - a pairing-setting unit (24A, 24B, 24C) that pairs each of the plurality of air conditioner bodies and each of the remote controllers (14A, 14B, 14C), wherein - the pairing-setting unit (24A, 24B, 24C) has a main machine registration function that registers a pair of the air conditioner body and the remote controller (14A, 14B, 14C), out of the conditioner bodies (12A, 12B, 12C) and the remote controllers (14A, 14B, 14C), as a main machine, and a sub machine registration function that registers the air conditioner body, which is registered as a main machine out of the air conditioner bodies, and a remote controller (14A, 14B, 14C) which is not registered as the main machine, as a sub machine, - a mode of operating the air conditioner body that is the main machine with the remote controller (14A, 14B, 14C) after registration of the main machine and the sub machine by the pairing-setting unit (24A, 24B, 24C) is defined as a main-machine operation mode, while a mode of operating the air conditioner body that is the sub machine with the remote controller (14A, 14B, 14C) is defined as a sub-machine operation mode, and