The mechanical wear of four Al-Mg-Si alloys : A(4.33% Mg-2.7% Si) , B (4.33% Mg -1.56% Si) ,C (4.33% Mg -1.17% Si) and D (4.33% Mg-5.4% Si) is investigated . Hardness of these alloys are measured for as cast ,homogenized and aged condition .Both homogenizing and aging temperatures are determinedfor these alloys . The best homogenizing temperature isfound to be 540 c and the proper200oc. The mechanical wear rate for,and aged alloys at loads 8.5 N,17aging temperature isas cast ,homogenizedN,34 Nand 51 N isinvesigated. A transition in the wear rate is observed at 34load .In general as aging time increases ,weardecreases giving minimum corresponding to best condition ,after which ,the wear rate increases astime increases due te overaging .agingHardness and plasticity affect greatly the wear rate.Hardness is important at light wear loads, while plasticityeffect is very important at heavy operating loads. It isnoticed that thermal properties of the precipitating phaseeffect greatly the wear rate. Precipitates with low thermal