Aerogels are known for their ultra-lightweight and high thermal insulation properties. Among a variety of inorganic and organic materials, polyimide (PI) compounds with high thermal stability, excellent chemical resistance, and superior mechanical flexibility have drawn great attention for development of high-performance aerogel materials. However, the majority of reported PI aerogels are in the form of bulk monolithic, which suffers from lack of drapability, conformability, machineability, and formability. Given this background, the focus of this research is to establish a platform for designing and developing a novel class of aerogel materials known as PI aerogel films to address the above challenges. Through controlling the material and processing parameters, PI aerogel films with controlled shrinkage, tailored nanostructured assembly, enhanced flexibility, tunable dielectric and electrical properties, along with improved thermal stability, are developed. To bring further multifunctionality into these aerogels, the addition of various nanofillers, such as graphene nanoplatelets and carbon nanotubes, is explored for the development of PI aerogel composite systems. To show the capability of these aerogels for practical fields, their potential application for emerging fields, namely thermal management of microelectronics, environmental remediation, and energy storage devices, is demonstrated. This research can therefore pave the way for the development of the next generation of aerogel materials.