Aerogel is a solid material with three-dimensional nanoporous network with gaseous mediums dispersed in its pores. With low density, high porosity and low thermal conductivity, aerogels are widely used in aerospace, electronic communication, flame retardant and thermal insulation, energy storage, adsorption, catalysis and sensing. This paper investigated the research progress of polyimide aerogels in recent years, discussed the preparation, structure-function relationship of polyimide aerogels, and pointed out that the future development of polyimide aerogels can start from improving the mechanical strength and reducing the thermal conductivity, and provided reference for the application of polyimide aerogels in thermal insulation and other fields.