Abstract: Under the background of the "dual carbon" goals, the development of green and efficient energy storage materials has attracted widespread attention. Biomass-derived carbon materials have emerged as promising electrode candidates for supercapacitors due to their abundant availability, low cost, and structural diversity. This review summarizes the preparation methods of biomass carbon from various sources, including plants, animals, and microorganisms, analyzes the regulatory mechanisms of physical activation and chemical activation on pore structure, and discusses the types, techniques, and effects of heteroatom doping, as well as the relationship between heteroatom doping and electrochemical performance. It focuses on summarizing the doping strategies of heteroatoms such as nitrogen (N) and sulfur (S), along with their enhancement mechanisms on conductivity, wettability, and pseudo-capacitance, and the progress in their applications. Although significant progress has been made, challenges remain in understanding doping mechanisms, controlling doping configurations, and achieving scalable production. Future efforts should focus on mechanism clarification and process optimization to promote the practical application of biomass carbon materials in high-performance energy storage systems.