AI203/TiA1 composites were fabricated by in-situ reaction synthesis using Ti, A1, TiO2 and Sm203 as starting materials. Effect of the doping Sm203 on the microstructures and properties of the A1203/TiA1 composites was analyzed by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and universal properties tests. The results show that the phases of the Sm203-doped composites are mainly composed of ）,-TiA1/a2-Ti3A1 matrix and reinforcing phases of A1203 and SmA1. The microstructures of A1203/TiAI composites are significantly refined with doping Sm203. Doping Sm203 has a positive effect on improving the mechanical properties of AlaO3/TiA1 composites. When the Sm content is 5% （mass fraction）, the flexural strength and fracture toughness reach the maximum values of 658.9 MPa and 10.13 MPa＇m~/2, respectively.
