The invention discloses an aluminum alloy and a preparation method and application thereof. The aluminum alloy comprises the following components in percentage by weight: 4-9% of silicon, 0.5-1.5% of copper, 0.3-1% of iron, 0-0.1% of rare earth elements, 0-0.3% of titanium, 0-0.5% of magnesium, 0-0.05% of boron, 0-0.1% of manganese, 0-0.1% of zirconium, 0-0.1% of chromium, 0-10% of zinc, 0-0.05% of strontium, 0-0.1% of lithium, 0-0.005% of vanadium, and 77.095-95.2% of aluminum. The aluminum alloy, provided by the invention, is excellent in comprehensive mechanical performance, higher in strength and hardness and higher in ductility, and can be machined to structural elements having various shapes and thicknesses. Above all, the aluminum alloy, provided by the invention, is excellent in heat conductivity. The aluminum alloy, provided by the invention, is suitable for serving as a structural material having higher requirements on the heat conducting performance, and in particular, is suitable for serving as a structural part of an electronic product.