Abstract: It is an atmospheric environment with an average pressure as 600 Pa of CO₂ and a minimum temperature of -123 ℃ in Mars. Ultra-low quality and high efficient thermal insulation material is the key material for the thermal control system of Mars Rover to ensure the normal operation of electronic components. Aerogel is the solid material with the lowest thermal conductivity in the atmospheric environment. Therefore, it is the best insulation material choice for the thermal control of Mars Rover. To meet the need of Mars Rover, a low density nano-aerogel insulation material with density of less than 30 kg/m³ has been developed in this article. The preparation process of low density aerogel and composite materials, and the supercritical CO₂ drying and ultra-low density aerogel composite’s being machined process are studied. The thermal physical properties, vacuum volatiles, the properties in the thermal cycling, thermal vacuum and other thermal environments are also characterized. The results show that the ultra-low density nano-aerogel insulation material has excellent structural and heat insulation stability in the Martian environment, which can meet the application requirement of space exploration. The material has good mechanical property and excellent thermal insulation property. The thermal conductivity of the low density aerogel composites is 0.0066 W/（m·K）at room temperature in Martian atmosphere which has been applied the Mars Rover in China.