The ever-increasing energy demand and fossil energy consumption accompanied by the worsening environmental pollution urge the invention and development of new, environmentally friendly and renewable high-performance energy devices. Among them, the supercapacitor has received massive attention, and the various electrode materials and polymer electrolytes have been exploited. The carbon-based electrodes and electrolytes derived from biomass are highly trusted as idea candidates for supercapacitors due to their attractive structure, abundance, low cost, renewability, and environmentally friendliness. This review will highlight the available characteristics of materials, synthetic strategies, and improvement approach of biomass-derived electrodes and electrolytes for application in supercapacitors. Future relative research trends also will be briefly discussed.