The work aims to explore application of SiO2 aerogel in thermal-insulating coating, and improve thermal insulation performance and heat resistance by taking advantage of its low thermal conductivity, low density, high porosity and low refractive index. Resin of lower heat absorptivity and filler of excellent thermal insulation performance were selected as raw materials of thermal-insulating coating by screening different types of water-base resin and functional filler. Thermal insulation performance of thermal-insulating coatings with different mass fractions of SiO2 aerogel was studied with homemade thermal insulation device and thermal conductivity measuring instrument. Phase structure and group change of the coatings heated to 200, 300 and 400 ℃ were studied in FT-IR and XRD methods. Water-based acrylic resin contained less endothermic groups, and its equilibrium temperature was 0.8 ℃ and 1.8 ℃ lower than that of polyurethane resin and epoxy resin respectively in same illumination conditions. It was more suitable to be used as film-forming materials of SiO2 aerogel heat insulation coating. As mass fraction SiO2 aerogel increased, heat insulation performance first improved and then reduced. The heat insulation performance was the best when the SiO2 aerogel mass fraction was 5%, insulating performance and temperature might reduce by 12 ℃. Meanwhile, the heat insulation performance improved as the SiO2 aerogel increased. When the mass fraction of SiO2 aerogel was 7%, the coating could maintain good properties at 400 ℃. SiO2 aerogel can improve the heat insulation performance and heat resistance of thermal-insulating coating significantly, laying the foundation of its multidisciplinary application.