An electric compressor, wherein an inverter device, which controls the operation of an electric motor by commands from an external control unit, is provided with a drive IC which computes drive signals of the electric motor based on the same, a switching circuit which converts the drive signals to rotation control signals of the electric motor, and an output signal control IC which cuts off input of the drive signals to the switching circuit at the time of an abnormality and wherein, furthermore, the drive IC is provided with a comparator which compares drive signals which are input to the switching circuit and computed values of the drive signals at a control unit inside the drive IC and, when the drive signals and the computed values do not match, the comparator makes the output signal control IC cut off input of the drive signals to the switching circuit.