The invention relates to a foamed-metal based high-temperature phase change heat storage composite material and a preparation method thereof, which relate to the technical field of heat storage materials. The composite material is characterized by comprising a foamed metal framework material which is attached with a solid-liquid phase change heat storage material when the temperature is more thanor equal to 600 DEG C, and a high temperature phase change heat storage material which accounts for 60 to 95 percent of the total weight. The composite material has the advantages of quick heat storage and release, high heat storage density, good heat conductivity and small volume shrinkage; besides, the composite material has wide applications, and is applicable to various fields of solar energyheat power generating systems for a space station, solar electrical energy generation, high temperature waste heat recovery and the like, particularly to a heat absorber of a space solar energy heat power generating system; and the preparation method is simple and convenient, has high recombination rate, and is easy to guarantee the product quality.