Abstract The Present paper has focused on properties of Carbon Nano Tubes (CNTs) reinforced aluminium metal matrix Nano composites. These Nano composites are fabricated by using stir method by varying the CNT reinforcement weight percentage (0.4%, 0.7% and 1.1%) of size 30 nm in Al 5056 matrix. To study its properties, the fabricated specimens are tested for the properties such as tensile strength, hardness, toughness and density. The properties of the Nano composites are found to be greatly influenced with increasing of weight percentage of reinforcement. With mixing of different weight proportion reinforced particles by stir casting process, nearly 25% increase in tensile and hardness strength of composites. The experimental values obtained from tests more useful in the development of Nano composites for different applications.