[en] Aluminium matrix composites reinforced with molybdenum aluminide nanoparticles were synthesized by ball milling and reactive sintering of the mixture of aluminium and 10 wt% hydrated molybdenum oxide powders. Sintering the as milled powder in air below 750 deg. C produced MoAl₁₂ intermetallic compound nanoparticles, at 750 deg. C produced a mixture of MoAl₅ and MoAl₄ nanoparticles and at 800 deg. C under Argon atmosphere produced predominantly MoAl₄ intermetallic nano-particles in the Al matrix. The powder compacts sintered in air below 750 deg. C produced MoAl₁₂ whereas at 750 deg. C or above formed the Al matrix composite reinforced with the MoAl₅ nanoparticles. These nanoparticles become agglomerated to take up some irregular shaped flakes in the metal matrix. The reaction between Al and hydrated Mo oxide powders was found to be a favorable way to produce predominantly a particular Mo-Al intermetallic compound at a particular temperature. The Al₂O₃ particles formed as another reaction product, in all the above reactions, remain distributed in these composites. The composites thus formed were characterized by SEM-EDS, DTA, XRD and TEM analysis