Abstract: Purealuminum matrix Al₃Ti particle composite was made by a new in-situmet hod involvingreactions between Al and TiO₂ which was stirred into molten metal. The size of the reinforcement Al₃Ti particle which is homogeneous in the pure Al matrix is 2～3 m. The combination between Al₃Ti and Al matrix is very well. When the amount of TiO₂ is 30wt% and the reaction temperature is 920℃, the streng th and hardness of the composite are higher than those o f purealuminum-matrix by 71.5% and 134%, respectively. However, the ductility of the composite is slightly lower than that of aluminum-matrix.