To provide an air conditioner preventing dew condensation at blowout ports of indoor units of the air conditioner connected with an outdoor unit and a plurality of the indoor units different in the types, and also to provide its control method.

The air conditioner is equipped with: the outdoor unit having a compressor for compressing coolant and an outdoor heat exchanger; a plurality of the indoor units connected to the outdoor unit and having indoor heat exchangers; and a control device for controlling operation of the outdoor unit and the indoor units. The control device stores the total operation capacity which is a total of operation capacities of all the indoor units (S4), and stores indoor units having smaller loads on cooling performance than those of other indoor units or a combination of the indoor units as a first indoor unit group (S4). If a total of operation capacities of the first indoor unit group during the operation is not more than a predetermined proportion of the total operation capacity (S7), a target low pressure value of the compressor is increased (S13).