Solid-state additive manufacturing offers significant potential for producing lightweight Al–Cu–Li alloy components in aerospace applications. In this study, Al-Cu-Li alloy was successfully fabricated using friction surfacing deposition additive manufacturing (FSD-AM). The FSD process produced a unique microstructure characterized by fine, equiaxed grains with inhomogeneous grain sizes distribution across the deposited layers, contributing to excellent ductility and moderate strength. Notably, ultrafine-grained bands formed at the interfacial junctions between layers, exhibiting a distinct preferred orientation compared to the adjacent regions. Thermal cycles during FSD transformed the deformed grains into recrystallized grains and promoted grain growth, influencing overall microstructural characteristics. TEM analysis revealed a high density of dislocations, along with the presence of multilayer-structured T 1 phase in the as-deposited material. Post-treatments, including direct aging and solution treatment followed by aging, reduced tensile strength. However, pre-rolling after solution treatment significantly enhanced the strength due to precipitation of high-density T 1 phases during subsequent aging. This work demonstrates the potential of FSD and optimized post-treatment strategies to tailor the mechanical properties of Al-Cu-Li alloys for advanced engineering applications.