Nanocellulose is a renewable and biocompatible nanomaterial with a high strength, low density, and tunable surface chemistry. Since a lot
of hydroxyl groups are present on the surface of the nanocellulose, this gives them various surface chemistries that can be tailor-made for specific application. This unique property makes them a promising candidate for various applications. Nanocellulose aerogels have gained considerable interest in the scientific community globally due to their renewability, good mechanical properties, low density, high porosity, natural biodegradability, and environmental friendliness. These fascinating properties makes them an attractive material in environmental and engineering applications. This chapter reviews recent attempts to apply nanocellulose aerogels as efficient materials for thermal insulation, flame retardancy, EMI shielding, oil absorption etc.