The effect of the additives, Y2O3 and MgO, on the sintering and properties of Al2O3-TiC composites was investigated. It is known that MgO is used as additive for improving densification and Y2O3 is applied as sintering aid. In this study, the amounts of TiC were varied in the range of 30-47 wt%. The 0.5 wt% MgO and also varied amounts of Y2O3 from 0.3 to 1 wt% were added into the composites. The sintering of Al2O3-TiC composites was performed in a graphite- heating element furnace at different sintering temperature, 1700 and 1900°C, for 2 hr under an argon atmosphere. The results demonstrated that the properties of the composites sintered at 1700°C were much better than those sintered at 1900°C. The comparisons on physical properties, mechanical properties and microstructure of composites with and without additives were reported. Comparing with other samples, Al2O3-30wt%TiC composites with 0.5wt% MgO and 1 wt%Y2O3 exhibited the highest density of approximately 98% of theoretical and flexural strength of 302 MPa.