This vehicle air-conditioning device has a compressor; an outside heat exchanger; a water-to-refrigerant heat exchanger; a heat release unit; a circulation means; and an air passage through which air is blown into a vehicle interior and in which the heat release unit is disposed midway, a send-out port for sending out the compressed refrigerant and an introduction port for introducing the refrigerant that has not been compressed being provided in the compressor, a first fit part that is fitted in the send-out port of the compressor, and a second fit part that is fitted in the introduction port of the compressor being provided in the water-to-refrigerant heat exchanger, and the compressor and the water-to-refrigerant heat exchanger being integrally joined by the first fit part and the second fit part being fitted.