Incorporating high-volume-fraction intermetallics into aluminum alloys is a typical way to enhance both room- and high-temperature strength, yet often sacrifices ductility. In this study, a novel Al–Si–Fe–Ni–Mn alloy with 35.6 vol.% and multi-scale heterogeneous IMCs was fabricated via powder metallurgy and thermo-mechanical processing. The alloy achieves an exceptional balance of room-temperature strength (477 MPa), ductility (8.2%) and high-temperature strength (277 MPa at 300°C), demonstrating remarkable strength-ductility synergy and superior heat resistance. This arises from a hierarchical architecture that coordinates deformation across multiple size scales. The findings presented herein provide fresh perspectives for the design of high-performance aluminum alloys.