Abstract: ZrC-SiC-C/C composites were fabricated by precursor infiltration and pyrolysis method (PIP) using the C/C with a low density as performs. The microstructure and ablation performance of the composites were investigated, and the anti-oxidant ablation behavior was discussed, particularly. The results show that ZrC-SiC dual ceramic phases are dispersed in the matrix, and a good interface between different phases is obtained; ZrC-SiC-C/C composites have an excellent anti-oxidant ablation performance. After ablation at 2 200℃ for 120 s by plasma flame, the linear and mass ablation rates of composites are 1.67×10^-4 mm·s^-1 and 6.04×10^-4 g·s^-1, respectively. When the ablation temperature is 2 200℃, ZrO₂-SiO₂ binary eutectic systemas a oxide film is formed on the surface, which can effectively prevent the infiltration of oxidation atmosphere, and reduce the denudation of flame on the material. When the ablation temperature rises to 2 500℃, aoxide membrane structure with the ZrO₂ as the outer layer and ZrO₂-SiO₂ binary eutectic system as the inner layer is generated on the surface. ZrO₂ layer can inhibit heat transmitting into interior, which contributes to form a dense oxide layer at the bottom.