Abstract: The graphite flakes/Al composite has the advantages of low density and high thermal conductivity, but it cannot be used as a kind of commercial electronic packaging material due to its poor mechanical properties at present. In order to improve the thermophysical properties of graphite flakes/Al composite, the SiC particles reinforced graphite flakes/Al composites were prepared via vacuum hot-pressing process. The effect of the different content of SiC on the thermal conductivity, coefficient of thermal expansion, and flexure strength of the SiC-graphite flakes/Al composites were studied. The result shows that the high-frequency vibration process contributes to the good orientation of graphite flakes in the composites. The SiC particles can significantly reduce the coefficient of thermal expansion, increase the flexure strength, and slightly decrease the thermal conductivity of the composites. However, as the volume fraction of SiC particles increases, many pores and defects are gradually foamed in the SiC-graphite flakes/Al composites, causing the decrease of the relative density. When the volume fraction of SiC and graphite flakes are 15vol% and 50vol%, respectively, the thermal conductivity in x-y plane, coefficient of thermal expansion and flexure strength of the SiC-graphite flakes/Al composite are 536 W/(m·K) and 6.4×10^-6 m/K and 102 MPa, respectively, exhibiting the best comprehensive thermophysical properties, which can be a kind of electronic packaging material with very commercial prospect.