Abstract: A hybrid vehicle and an air-conditioning system thereof. A heating part of the air-conditioning system may be provided with an electric heating device (120, 220) and a water heating device (130, 230), the electric heating device (120, 220) is turned on and the water heating device (130, 230) is turned off when the temperature of engine cooling water is lower than a preset temperature threshold, and the electric heating device (120, 220) is turned off and the water heating device (130, 230) is turned on when the temperature is higher than the preset temperature threshold. A refrigerating part of the air-conditioning system may comprise a mechanical compressor and selected auxiliary power units (20) as a portion of a plurality of auxiliary power units, and when cold air flow needs to be supplied, an air-conditioning controller (110, 210) sends an enabling instruction to a power controller (61) to control the selected auxiliary power units (20) to enter a forced working mode.