<p>This paper focuses on the preparation of aluminum matrix diamond composites by laser additive manufacturing technology and explores the influence of different diamond contents (0%, 1%, and 5%) on the mechanical properties and wear properties of aluminum matrix composites. Above all, the optimization of manufacturing parameters is carried out, with the changing of the laser scanning space and scanning speed, the densities of specimens under different parameters are tested and the surface quality is observed, and the optimal manufacturing parameters are selected. Additionally, the mechanical and wear specimens are additively manufactured based on the optimal manufacturing parameters, and the influence of diamond content on the mechanical and wear properties of the specimens is investigated. Ultimately, the data are analyzed and it is concluded that the strength, toughness, and ductility of the additively manufactured composites show a decreasing trend with the increase of diamond content (0 wt.% to 5 wt.%), and the ultimate tensile, compressive and flexural strengths are decreased by 40.33%, 33.39%, and 44.14% respectively; the yield strength is decreased by 7.01% and the elongation is decreased by 89.63%. What is more, the flexural modulus and wear resistance of the composites are enhanced with the addition of diamond, the flexural modulus is increased by 15.41% and the wear material volume is decreased by 83.3%.</p>