To provide the controller of an air conditioner which can suppress the peak power without giving the user uncomfortableness.

In this controller of air conditioner, the main controller 60 controls water spray controll 51 and 52 when the power consumption gets over the specified value, and sprays water to a heat exchanger working as a condenser from its nozzle so as to cool the heat exchanger. Thereby, since the power load ca be reduced without stopping a compressor 27, the peak power can be suppressed without giving the user the uncomfortableness of interruption of air conditioning operation.