This paper introduces using silicon resin as a ramjet engine insulation layer of matrix material, with YJ short fiber or fabric as reinforced two insulation formula ablative properties of materials. The influence of content of YJ short fibers and the mass ratio of silicone resin/ fiber fabric, on the insulation ablation rate and the process performance was studied. The results show that YJ short fiber is 4 phr, the comprehensive performance of ablation and silicon resin/ YJ short fiber/ zirconia formula was the best, and the mass ratio of silicone resin and the fabric is 1. 1 ∶1, silicone resin/ fiber fabric formulations of oxyacetylene ablation rate is the smallest, with only 15. 2 μm/ s. 20 seconds compression ratio engine ground test results show that the two formulations, insulation of ramjet engine implemented effective thermal protection.