PURPOSE: To obtain an Al alloy with superior strength and toughness, by adding specified amounts of transition elements such as Mn, Cr and Zr to an Al-Mg-Si alloy.

CONSTITUTION: 0.05W0.8% Mn and 0.05W0.35% Cr and/or 0.05W0.20% Zr are added to an Al-Mg-Si alloy contg. 0.9W1.8% Si, 0.8W1.4% Mg and 0.4W1.8% Cu and having relation represented by Si content-Mg content/1.73≥0.3%. An Al alloy with superior strength and toughness suitable for use as a material for a baseball bat, a tent pole, a bobbin, bicycle parts, etc. is obtd.