A vehicular air-conditioner wherein when a detected temperature of an inverter temperature sensor (22g) exceeds a predetermined value, an inverter (6) driving an electric motor (4) of an electric compressor (3) operates in an overheat protection mode for driving the electric motor by a heat protection speed different from the speed command value from the air-conditioning controller (20), secures the refrigerant flow rate, and cools itself. At this time, when a condenser fan (8) or vehicle compartment blower (14) is stopped by passenger operation or air-conditioning control, it is operated to promote the heat exchange at the heat exchangers, whereby it becomes possible to prevent an increase in the refrigerant pressure in the condenser (7) and prevent frost at the evaporator (11) and possible to protect against failure of function of the refrigeration cycle (2).