VEHICLE AIR-CONDITIONING DEVICE

A vehicle air-conditioning device is provided which is capable of eliminating inconvenience due to a reduction in heating capability when changing from heat absorption from outdoor air to heat absorption from a heat medium. A heat-generating equipment temperature adjusting device has a heat medium heating heater and a refrigerant-heat medium heat exchanger . The vehicle air-conditioning device has first and second heat medium heat absorption/heating modes to let a refrigerant discharged from a compressor radiate heat in a radiator , decompress the refrigerant from which the heat has been radiated, and then let the refrigerant absorb heat in the refrigerant-heat medium heat exchanger. When the temperature of the heat medium is a predetermined threshold T or less upon changing from a heating operation to the first and second heat medium heat absorption/heating modes, the heat medium is heated by the heat medium heating heater before the changing.