The performances of energy storage modes are experimentally analyzed in the artificial environment in order to study the effect of energy storage modes for defrosting of air source heat pump with phase change energy storage. Results indicate that suction and discharge pressures are stable at 038 MPa and 165 MPa under the series energy storage mode, and suction and discharge temperatures are 6.9℃ and 75.0℃ respectively. However, the suction and discharge pressures are as low as 012 MPa and 116 MPa in parallel and single energy storage modes individually, and the discharge temperature is up to 1225℃. In addition, in series energy storage mode, the phase change material can completely change from solid to liquid in energy storage process. The temperature difference is about 18.0℃ for indoor coil, and the input power to compressor is 825W. Therefore, the system pressures and temperatures are most stable in the series energy storage mode and the time for energy storage is short, which can meet the need of defrosting energy.