To provide a castable aluminum alloy capable of preventing seizure between the aluminum alloy and a mold when cast and having excellent yield strength and elongation and to provide a highly tough aluminum cast therefrom.

The castable aluminum alloy comprises 6.0 to 11.0 wt.% Si, 0.1 to 0.5 wt.% Mg, and 0.1 to 0.5 wt.% Cr, with the balance Al and unavoidable impurities containing 0.42 wt.% or less Fe. The aluminum alloy excellent in castability, yield strength, and elongation can be obtained by adding a predetermined amount of Cr as an anti-seizure material.