There is provided an electric compressor capable of being actuated rapidly. During the time when the operation of an automotive air conditioner is stopped, by heating a motor 12, a refrigerant on the outlet side 11b of a compressor body 11 is heated. Thereby, the temperature of refrigerant on the outlet side 11b is raised, and the refrigerant is prevented from being liquefied on the outlet side 11b of the compressor body 11, by which the automotive air conditioner can be actuated rapidly. Besides, by rotating the motor 12 at the number of revolutions lower than that at the time of normal operation, the refrigerant liquefied on the outlet side 11b of the compressor body 11 may be pushed out.