Multifunctional phase change composites are in great demand for all kinds of industrial technologies and applications, which have both superior latent heat capacity and excellent solar-thermal conversion capability. In this research, biomimetic phase change composites are made by inspired by natural systems, successfully getting the high thermal conductivity of carbon foam and magnetism of composites together, to establish a novel solar-thermal energy storage method. The morphology and the thermal characteristics of biomimetic phase change composites have been characterized. The results showed that the maximum storage efficiency of the biomimetic phase change materials increased by 56.3% compared to that of the based materials, and it can further be improved by the application of magnetic field. Meanwhile the heat transfer process of solar-thermal conversion and energy storage in biomimetic porous structure under the external physical fields has been explained by simulation. Thus, the magnetic field-induced method applied in this research has better solar-thermal energy storage characteristics within a porous structure by dynamically controlling the magnetism, which has potential uses for various sustainable applications, including waste-heat recovery, energy conservation in building, and solar-thermal energy storage.