New light-weight Al-alloys are important nowadays for energy saving and improving fuel efficiency in the transportation sector. Al-Mg-Si alloys referred to 6xxx of wrought alloys, are shaped in a soft condition, usually by extrusion or rolling, and are then age hardened to their final strength. Over the last decade, several cast alloys of Al-Mg-Si system have been developed. These alloys have interesting mechanical properties with YS of 160 MPa, UTS exceeds 280 MPa and elongation up of 14% in as-cast condition after high pressure die casting (HPDC) for parts with an average wall thickness of 4-6 mm. Furthermore, Al-Mg-Si alloys have high corrosion resistance, good welding properties after HPDC. The addition of scandium to aluminum can substantially increase strength, provide precipitation hardening, and effectively refine the grain structure. The effect of Sc as an additional element to the AlMg5Si2Mn alloy (close to a commercial one) on the mechanical properties and microstructure was investigated using high-resolution scanning electron microscopy (SEM), nanoindentation and tensile testing technique.Taking in account a high price of Sc and Sc-containing master alloys, a partial substitution by Zr (due to the possible formation of the simple Al3(Sc,Zr) and complex Al3(Sc1-x,Zrx) dispersoids) is proposed. Several new alloys containing Sc and Zr up to 0.2 wt.% have been molded using high pressure die casting technique. The average microhardness value increases up to 9% compared to the base alloy. (Sc+Zr) addition gave promising results in term of yield strength as well as uniform elongation, and 50 % respectively increase compared to the base alloy.