This study investigates various processing approaches, interface characteristics, and mechanical properties of an aluminum (Al) matrix composite reinforced with additively manufactured (AM) 316L stainless-steel (SS) lattice. The AM-316L-SS lattice, boasting a 30 % infill density, was fabricated using the laser powder bed fusion technique. The Al-matrix was integrated with the AM-316L-SS reinforcement through experimentation involving pre-stirring of the molten Al under pressurized and unpressurized die-casting conditions. A well-bonded interface, with cohesive regions, was obtained in the pre-stirred structures. In contrast, regions of decohesion were displayed in cast structures without pre-stirring, leading to the presence of pores and the manifestation of imperfect bond interfaces. Compression tests conducted on the sound composite demonstrated enhanced mechanical properties, with a compressive strength of approximately 163 MPa, significantly higher than that of the pure Al-matrix (approximately 80 MPa). Localized interface cracking was initiated by stress gradients and plastic deformation, leading to microcrack propagation into the Al-matrix.