Ultra-high temperature composite ceramic matrix composites ZrC-SiC, ZrB₂-ZrC-SiC and HfB₂-HfC-SiC were fabricated by precursor infiltration and pyrolysis method. The ultra-high temperature ceramic phases in the materials were characterized by submicron/ nanometer uniform dispersion distribution. Ablation behaviors of ZrC-SiC, ZrB₂-ZrC-SiC and HfB₂-HfC-SiC matrix composites under atmospheric plasma and on-ground arc-jet wind tunnel were investigated comparatively. The main factors that affect design for ultra-high temperature composite ceramic matrix composites were summarized. The result shows that, compared with traditional SiC-based composites, ultra-high temperature composite ceramic matrix composites have a solid-liquid two-phase dense oxide film formed in situ on the surface of the composites after ablation. Synergistic effect of the two phases has achieved effects of erosion resistance and oxidation resistance, which plays a very important role in hindering the loss of liquid SiO₂ and greatly improves the ultra-high temperature ablation performance of the materials. On this basis, the important factors that should be considered in the matrix design of ultra-high temperature composite ceramic matrix composites are obtained. The above results have instructional significance for the ultra-high temperature and the limited life application of ceramic matrix composites.