The aim of the present work is to study the dry sliding wear behaviour of A356/Al2O3nanocomposites at both roomand elevated temperatures. Dry wear tests were conducted at several sliding speeds at room temperature. Wear test results showed that The A356/Al2O3 nanocomposites exhibited lower wear rates at both room and elevated temperatures when compared with theA356 monolithic alloy. Increasing the volume fraction and/or reducing the Al2O3 nanoparticles size reduces the wear rates of the A356/ Al2O3 nanocomposites. Introducing theAl2O3 nanoparticulates to theA356 aluminum alloy assisted in increasing the mild-to-sever wear transition temperature. The composites exhibited transition temperature between 150 and 200 oC, while the unreinforced alloy exhibited a transition temperature between 100 and 150 oC.