The filamentous M13 viruses are widely used as a bio-template to assemble many different functional structures. In this work, based on its shape anisotropy, reasonable aspect ratio (length to diameter of ≈130), and low density, freestanding, bulk 3D aerogels are assembled from M13 for the first time. These ultralight porous structures demonstrate excellent mechanical properties with elastic behavior up to 90% compression. Furthermore, as the genome of M13 virus can be rationally engineered so that proteins on its capsid or ends can specifically bind to various inorganic materials, aerogels made from inorganic-complexed M13 structures with versatile functionalities are also developed. As examples for mono- and multi-component structures, M13-Ru and M13-CoFe2O4 are explored in this work. This method enables the production of a wide variety of freestanding inorganic material aerogels with extensive opportunities for bio-scaffolds, energy storage, thermoelectrics, catalysis, hydrogen storage applications, etc., in the future.