Different milling conditions have been tried to produce nanoparticles of TiB 2 to be used as reinforcement in Al matrix composite materials. The milling of TiB 2 compounds leads to a decrease of both the crystallite size and the particle size. Moreover, we demonstrate that the use of optimized conditions with a vibratory miller allows – in a short period of time – the direct synthesis of nanoparticles of TiB 2 starting from the elemental powders (Ti and B). Then TiB 2 reinforced Al composite was fabricated using a simple powder metallurgy process followed by free sintering under controlled atmosphere. The influence of (i) the nanometric TiB 2 particles grain size and (ii) their volume fraction on the hardness and Young's modulus, measured from nanoindentation tests, has been analyzed.