In this research novel approach to the selection of the best suitable composition of nanocomposite from the various alternatives of nano-Al2O3/Al6061 using multi-criteria decision-making, techniques are presented. Low strength and hardness limit the use of Al6061 in moderate to high-stress applications such as in aerospace and automobiles. To overcome this deficiency, multi-characteristics Al2O3 nanoparticles are successfully reinforced in various wt. % to Al6061 matrix to fabricate novel Al2O3/Al6061 nanocomposites on aluminum stir casting furnace. That results in an improvement in mechanical properties at a different order of importance and various material cost. Hence it is essential to determine the best suitable alternative of nanocomposite and corresponding optimum quantity satisfying application requirements. Therefore, to tackle the difficulty of best suitable composition selection at required order of importance, multicriteria decision-making techniques such as TOPSIS and EXPROM2, was implemented and rankings are obtained. Weight criteria are determined using the AHP model. Comparative study of all MCDM is carried out by spearmen’s rank correlation. The best material found is 4A (4% Al2O3 reinforcement). MCDM analysis was found satisfactory for material selection problems.