AZ31/AZ91 hybrid alloy nanocomposite containing Al 2 O 3 nanoparticle reinforcement was fabricated using solidification processing followed by hot extrusion. The nanocomposite exhibited similar grain size to the monolithic hybrid alloy, reasonable Al 2 O 3 nanoparticle distribution, non-dominant (0002) texture in the longitudinal direction, and 25% higher hardness than the monolithic hybrid alloy. Compared to the monolithic hybrid alloy (in tension), the nanocomposite synergistically exhibited higher 0.2%TYS, UTS, failure strain and work of fracture (WOF) (+12%, +7%, +99% and +108%, respectively). Compared to the monolithic hybrid alloy (in compression), the nanocomposite exhibited higher 0.2%CYS and UCS, and lower failure strain and WOF (+5%, +3%, −7% and −7%, respectively). The beneficial effects of Al 2 O 3 nanoparticle addition on the enhancement of tensile and compressive properties of AZ31/AZ91 hybrid alloy are investigated in this paper.