The present invention discloses a method for fabricating aerogels, a method for fabricating surface-modified aerogels, and a method for fabricating biocomposites. Take the fabricating method of biocomposites for example, first, a precursor solution is provided and the precursor solution comprises a hydrophilic ionic liquid, a catalyzed hydrolysis and/or condensation reagent, at least one biomolecule. Next, a curing process is performed for the precursor solution to hydrolyze and polymerize the at least one alkoxide monomer and/or aryloxide monomer to wrap at least one biomolecule and thus form biocomposite. Afterwards, an extracting process is performed by a solvent for the biocomposite to substitute the ionic liquid in the biocomposite. Finally, a drying process for the biocomposite is carried out after the extracting process so as to remove the solvent in the biocomposite. Therefore, the biocomposite is formed.