6Paraffin has a great potential as the phase change material (PCM) to be applied in many energy-related 7 applications, such as thermal energy storage and thermal management, due to its appropriate phase change 8 temperature and large latent heat. The heat transfer characteristics during phase change of paraffin play a 9 very important role in determining the thermo-fluidic performance of the systems. However, the drawback 10 of small thermal conductivity of PCM hampers its application. In the present study, the composite PCM 11 was fabricated by using copper foam to enhance the thermal conductivity of paraffin, and an experimental 12 setup was built to study the phase change heat transfer characteristics of composite PCM. The evolvement 13 of solid-liquid interface and temperature variation during the melting process were experimentally 14 investigated, and the experimental results were compared with the numerical results obtained by the 15 two-temperature energy model. It was indicated that there was a quite large temperature difference between 16 the ligament of copper foam and paraffin, which was due to the thermal non-equilibrium effect in heat 17 transfer between the paraffin and copper foam. Good agreement between the experimental and numerical 18 results showed that the heat transfer characteristics could be well depicted by the two-temperature energy 19 model, which can be further used to depict the heat transfer in thermal energy storage or temperature 20 management using composite PCM. 21 22