An elastic thermal insulation coating with low density and high-temperature resistance was developed for applition onto carbon fiber composite case for solid rocket motors exposed to thermal environment, which has experienced static quartz lamp radiation test and arc-heated wind tunnel test for thermal protection performance evaluation. It is observed that the said thermal insulation coating provided such properties as density of 0. 62 g/ cm3, elongation in the range of 25%, and thermal conductivity in the range of 0. 18 W/ (m·K). The DSC test results indicated that the weight loss rate is 6. 6% at 401℃. The evaluation test has shown that the said thermal insulation coating of 1. 0 mm thickness exhibited superior thermal protection performance with case-to-coating interfacial temperature up to 77. 3℃ and back case surface temperature up to 44. 5℃.