SiO2 aerogel is an excellent thermal insulation material,which has excellent properties,due to its special network structure,such as high specific surface area,high porosity,low thermal conductivity and low density. However,the mechanical properties of SiO2 aerogel are fragile,which makes it difficult to prepare complex and miniature components by traditional manufacturing methods,which greatly hinders the development and application of SiO2 aerogel in the field of heat insulation. In this paper,flexible SiO2 aerogel composites were prepared by 3D printing direct writing technology. By studying the content of different polyvinyl alcohol solutions and sodium stearate,the optimal slurry ratio was found. The thermal conductivity of the printed flexible SiO2 aerogel composites at 100 ℃ is as low as 0.026 W/(m·K),and it has good compression performance,bending performance and hydrophobicity. This study provides a possibility for the large-scale application of SiO2 aerogel.