PURPOSE: To provide a protection control device for an air conditioner wherein protective operation of a high reliability compressor is performed and it is possible to judge whether the protective operation is performed owing to an overload or power supply voltage failure.

CONSTITUTION: A compressor protective device 8, through which a current from a failure detector 12 and a solenoid coil current passing through a contact (a) of a control relay 9 both flow, is opened upon overloading for protection while an ordinary current flows through the failure detector 12 via a contact (b) and upon voltage failure the relay 9 is turned off by a control circuit 11 for protection of the compressor. Further, the control circuit 11 thereupon confirms failure information and determines the cause of the protective operation based upon the on/off operation of the control relay and the failure information.