Spark plasma sintering is a rapid, low⁃temperature, high⁃density sintering technique that facilitates the fabrication of dense compacts while mitigating excessive grain growth and insufficient densification. This study systematically investigated the effects of sintering pressure on the microstructure and thermophysical properties of Al⁃0.6Si composites prepared by spark plasma sintering. The results show that sintering pressure strongly influences the properties of high⁃silicon aluminum composites. At a sintering pressure of 40 MPa, the Al⁃0.6Si composite exhibits the densest microstructure and the smallest average silicon⁃phase size. Its thermal conductivity is 130.35 W/(m·K), thermal expansion coefficient is 8.51×10⁻⁶ K⁻¹, Vickers hardness is 329.2 HV, density is 2.394 3 g/cm³, and relative density reaches 96.93%. These results demonstrate that optimizing the sintering pressure is an effective route to preparing high⁃performance composites for electronic packaging and provides process guidance for their fabrication.