An air conditioner system, comprising a compressor, an indoor heat exchanger, a first throttle device, and an outdoor heat exchanger connected in series in a main circuit, the air conditioner system further comprising a bypass pipeline, a bypass defrosting circuit and a throttle valve, wherein the main circuit is also provided with a first pipeline, a second pipeline, a heat exchanger, a first gas-liquid separator and a second gas-liquid separator, the bypass defrosting circuit is disposed between the compressor and the outdoor heat exchanger, one side of the heat exchanger is connected to the first pipeline between the first throttle device and the indoor heat exchanger, and the other side of the heat exchanger is connected to the second pipeline between the first throttle device and the outdoor heat exchanger, so that a refrigerant passing through the first pipeline and a refrigerant passing through the second pipeline can exchange heat in the heat exchanger; and the first gas-liquid separator is positioned in the second pipeline section between the heat exchanger and the indoor heat exchanger, and the bypass pipeline is disposed between the first gas-liquid separator and the compressor; and the bypass defrosting circuit is configured to perform defrosting operation on the outdoor heat exchanger in a heating process of an air conditioner wherein the throttle valve is disposed in the bypass defrosting circuit, when the outdoor heat exchanger needs to be defrosted, the throttle valve is configured to be opened, so that the refrigerant flowing out from the compressor performs the defrosting operation on the outdoor heat exchanger through the bypass defrosting circuit; and when the outdoor heat exchanger does not need to be defrosted, the throttle valve is configured to be closed, wherein the compressor is provided with the second gas-liquid separator, and the refrigerant flows back into the compressor after passing through the second gas-liquid separator, wherein the bypass pipeline is connected to an upstream of the second gas-liquid separator. wherein the main circuit is also provided with a first pipeline, a second pipeline, a heat exchanger, a first gas-liquid separator and a second gas-liquid separator, the bypass defrosting circuit is disposed between the compressor and the outdoor heat exchanger, one side of the heat exchanger is connected to the first pipeline between the first throttle device and the indoor heat exchanger, and the other side of the heat exchanger is connected to the second pipeline between the first throttle device and the outdoor heat exchanger, so that a refrigerant passing through the first pipeline and a refrigerant passing through the second pipeline can exchange heat in the heat exchanger; and the first gas-liquid separator is positioned in the second pipeline section between the heat exchanger and the indoor heat exchanger, and the bypass pipeline is disposed between the first gas-liquid separator and the compressor; and the bypass defrosting circuit is configured to perform defrosting operation on the outdoor heat exchanger in a heating process of an air conditioner wherein the throttle valve is disposed in the bypass defrosting circuit, when the outdoor heat exchanger needs to be defrosted, the throttle valve is configured to be opened, so that the refrigerant flowing out from the compressor performs the defrosting operation on the outdoor heat exchanger through the bypass defrosting circuit; and when the outdoor heat exchanger does not need to be defrosted, the throttle valve is configured to be closed, wherein the compressor is provided with the second gas-liquid separator, and the refrigerant flows back into the compressor after passing through the second gas-liquid separator, wherein the bypass pipeline is connected to an upstream of the second gas-liquid separator.