Abstract: SiC/Al composites with volume fraction of 45vol% and particle size of 80 μm were prepared by pressureless infiltration process. The microstructure of SiC/Al composites was observed by optical microscope and scanning electron microscope.The results show that the uniform distribution of enhanced phase particles in the matrix is observed in the SiC/Al composite, and there is poor pore and interface binding in the local microstructure.The Si elements in the matrix emerge in the form of cocrystalline Si. The C elements are relatively evenly distributed, mainly involved in the interfacial reaction with the Al matrix.Enriched regions of Mg and Si are present in the matrix, it is mainly due to the Mg₂Si phase precipitated during the infiltration process. Mg and O-rich reaction products exist near the interface, and the presence of various microstructure and phases in the composite affects the mechanical properties of the material.