The invention relates to a heat pump air-conditioning system. The heat pump air-conditioning system comprises a heat source heating unit and an intermediate working medium circulating unit and further comprises a jet refrigeration circulating unit which is connected with the intermediate working medium circulating unit through a heat exchanger. The heat source heating unit comprises a first heat source channel and a second heat source channel which are arranged in parallel, and one of the first heat source channel and the second heat source channel can be selected to be opened. One of the first heat source channel and the second heat source channel is connected with the jet refrigeration circulating unit, and the other one of the first heat source channel and the second heat source channel is connected with the intermediate working medium circulating unit through a heat interchanger. In a refrigeration mode of the heat pump air-conditioning system, the heat source channel connected with the jet refrigeration circulating unit is opened; in a heating mode of the heat pump air-conditioning system, the heat source channel connected with the intermediate working medium circulating unit is opened. The heat pump air-conditioning system is high in energy efficiency and beneficial to energy conservation and emission reduction.