<p>Aluminum matrix composites reinforced with SiC particles (SiCp/Al) hold great application potential in the aerospace field. Nevertheless, the high hardness and wear resistance of SiCp/Al also pose significant challenges for its processing. In this paper, the diamond wire cutting (DWC) process of the SiCp/Al (70 vol% SiC) was investigated for exploring the optimal cutting process considering the efficiency and surface quality. DWC experiments on SiCp/Al with high-volume fraction of SiC particles (70 vol% SiC) were conducted by an orthogonal experiment. The material removal processes of the Al matrix and SiC particles in DWC are analyzed according to scanning results of machined surfaces by scanning electron microscope and energy dispersive spectrometer. In addition, the effects of cutting parameters such as wire speed, workpiece rotation speed, and workpiece feed speed on the surface roughness of SiCp/Al workpiece were analyzed and discussed in detail. The results indicated that SiC particle fracture, particle pull-out, and Al matrix shear occur during the material removal process. The rotation speed of the workpiece has the most significant impact on surface roughness compared with other cutting parameters. This work can provide an efficient reference for the high-efficiency and high-quality cutting of SiCp/Al with a high-volume fraction of SiC.</p>