Supercapacitors, a novel type of energy storage devices, are becoming increasingly popular owing to their incredibly extended life cycle, increased power density, and rapid charging and discharging rates. The electrodes of supercapacitors are the primary determinant of their price and efficiency. Porous electrodes are still being developed and designed in an attempt to boost performance at a low cost. A sizable electrode featuring a significant mass augmentation is one of the interesting structural strategies to raise the supercapacitor’s density of energy. Carbon aerogels derived from biomass have been used recently to create thick electrodes for supercapacitors, both in their pure and composite forms with capacitive materials. Because these materials possess simple synthesis, minimal environmental impact, renewable, high adsorption, quick transport of electron/ion, and adjustable surface chemistry. Biomass-based carbon aerogels can be made from any source of biomass components using solgel, hydrothermal, and pyrolysis techniques. The activation of the carbon aerogel with chemicals such as CO2, KOH, ZnCl2, and NaOH is essential in improving its capacitance, porosity, and surface area. Here, we reviewed recently published studies on the synthesis of biomass-derived carbon aerogels from cellulose, lignocellulose, lignin, starch, tannin, and chitosan for use in supercapacitors.