To provide an air conditioning system improved in its capacity at low costs.

In this air conditioning system 1A, one main bathroom air conditioning device 2A and one auxiliary bathroom air conditioning device 2B are disposed on a ceiling panel 110 of a bathroom 101. In the air conditioning system 1A, the main bathroom air conditioning device 2A is operated according to an operation mode selected by a main operating portion 4, a communication is performed between the main bathroom air conditioning device 2A and the auxiliary bathroom air conditioning device 2B, the operation and non-operation of the auxiliary bathroom air conditioning device 2B is switched, and the auxiliary bathroom air conditioning device 2B is operated in a prescribed operation mode for assisting the main air conditioning device.