TaSi₂ was added into ZrB₂-20%SiC to get ZrB₂-10%SiC-10%TaSi₂. Then composites were oxidized in stagnant air at 1000℃,1200℃,1500℃ and 1650℃ for 5 min,15 min,30 min.The composites were prepared by hot pressed sintering (1950℃/30 MPa/30 min) and analyzed by X-ray diffraction and SEM.The weight change due to oxidation and microstructure were recorded. The results show the density and mechanical properties are increased by adding TaSi₂ into ZrB₂-20%SiC,but the oxidation resistance of ZrB₂-10%SiC-10%TaSi₂ is decreased above 1200℃.