Alloys of the Al - Mg system are characterized by an elevated corrosion resistance and ductility and good casting properties. The strength of these alloys depends considerably on the concentration of the main alloying element, namely, magnesium. Alloying with small amounts of transition metals, for example, Ti, Zr, Cr, Sc, affects markedly the structure and properties of Al - Mg alloys. The present work is devoted to the structure and properties of Al - Mg alloys alloyed with scandium.