In this study, SiC particles reinforced aluminum matrix composite was successfully fabricated using powder metallurgy technique followed by hot extrusion. The phases were identified by XRD and the microstructures were observed by SEM. The results showed that only Al and SiC phases existed in the composite, SiC particulates were well distributed in the aluminum matrix and the interface between Al and SiC was clean and well combined. Meanwhile, thermal conductivity and coefficient of thermal expansion of the composite were investigated, the research showed that thermal conductivity decreased as SiCp content increased because of poor thermal conductivity of SiCp and increased crystal defects forming during the fabrication process. And the same to thermal conductivity, coefficient of thermal expansion of the composite decreased as SiCp content increased because SiCp can acted as obstacles to the motion of dislocations, which can hinder the hot movement of electronics.