A heat pump air conditioning system, comprising: a compressor; an indoor unit heat exchanger, an outdoor unit heat exchanger and a throttling device; a refrigerant circulation loop, connecting the compressor, the indoor unit heat exchanger, the outdoor unit heat exchanger and the throttling device in series; a heat storage module, disposed in the refrigerant circulation loop; wherein a pipeline between the outdoor unit heat exchanger and the throttling device is a first pipeline, and the heat storage module is connected to and arranged on the first pipeline between the outdoor unit heat exchanger and the throttling device; the system further comprises a four-way valve; the four-way valve comprises a first connection end, a second connection end, a third connection end and a fourth connection end; the first connection end and the indoor unit heat exchanger are connected; the second connection end and an exhaust port of the compressor are connected; the third connection end and the outdoor unit heat exchanger are connected; and the fourth connection end and the suction port of the compressor are connected; characterised in that: a connection pipeline between the second connection end of the four-way valve and the exhaust port of the compressor is a second pipeline; the heat storage module is disposed on the second pipeline as well; and the second pipeline passes through the heat storage module; a first parallel pipeline is arranged at both ends of the heat storage module in parallel; one end of the first parallel pipeline is connected to a position of the first pipeline, where one end of the heat storage module is located; another end of the first parallel pipeline is connected to a position of the first pipe, where another end of the heat storage module is located; a first control valve is further provided and configured to control one of the heat storage module and the first parallel pipeline to be open and control another to be closed; and the first control valve is a first three-way valve, and is disposed at a position where the first parallel pipeline and the first pipeline are connected. a compressor; an indoor unit heat exchanger, an outdoor unit heat exchanger and a throttling device; a refrigerant circulation loop, connecting the compressor, the indoor unit heat exchanger, the outdoor unit heat exchanger and the throttling device in series; a heat storage module, disposed in the refrigerant circulation loop; wherein a pipeline between the outdoor unit heat exchanger and the throttling device is a first pipeline, and the heat storage module is connected to and arranged on the first pipeline between the outdoor unit heat exchanger and the throttling device; the system further comprises a four-way valve; the four-way valve comprises a first connection end, a second connection end, a third connection end and a fourth connection end; the first connection end and the indoor unit heat exchanger are connected; the second connection end and an exhaust port of the compressor are connected; the third connection end and the outdoor unit heat exchanger are connected; and the fourth connection end and the suction port of the compressor are connected; characterised in that: a connection pipeline between the second connection end of the four-way valve and the exhaust port of the compressor is a second pipeline; the heat storage module is disposed on the second pipeline as well; and the second pipeline passes through the heat storage module; a first parallel pipeline is arranged at both ends of the heat storage module in parallel; one end of the first parallel pipeline is connected to a position of the first pipeline, where one end of the heat storage module is located; another end of the first parallel pipeline is connected to a position of the first pipe, where another end of the heat storage module is located; a first control valve is further provided and configured to control one of the heat storage module and the first parallel pipeline to be open and control another to be closed; and the first control valve is a first three-way valve, and is disposed at a position where the first parallel pipeline and the first pipeline are connected. a connection pipeline between the second connection end of the four-way valve and the exhaust port of the compressor is a second pipeline; the heat storage module is disposed on the second pipeline as well; and the second pipeline passes through the heat storage module; a first parallel pipeline is arranged at both ends of the heat storage module in parallel; one end of the first parallel pipeline is connected to a position of the first pipeline, where one end of the heat storage module is located; another end of the first parallel pipeline is connected to a position of the first pipe, where another end of the heat storage module is located; a first control valve is further provided and configured to control one of the heat storage module and the first parallel pipeline to be open and control another to be closed; and the first control valve is a first three-way valve, and is disposed at a position where the first parallel pipeline and the first pipeline are connected.