Biomass-derived electrocatalysts for oxygen reduction in energy conversion devices are promising alternatives to platinum group metal (PGM)-based catalysts. These materials are derived from abundant, low-cost, and renewable biomass sources, offering sustainable and cost-effective solutions for applications such as proton exchange membrane fuel cells (PEMFCs), anion exchange membrane fuel cells (AEMFCs), and zinc-air batteries (ZABs). The focus of this review is on the development of PGM-free electrocatalysts with high performance for the oxygen reduction reaction (ORR), which is a critical process in fuel cells and batteries. The review highlights the importance of synthetic methods in determining the properties of these materials, including their specific surface area, porosity, and electrochemical activity. The results show that biomass-derived materials can achieve performance comparable to commercial PGM-free electrocatalysts, although further improvements are needed for practical deployment. The review also discusses the role of heteroatoms such as nitrogen and fluorine in enhancing the electrocatalytic activity of biomass-derived materials. Various synthesis methods, including hydrothermal carbonization, pyrolysis, and chemical activation, are explored for their effectiveness in producing high-performance electrocatalysts. The review emphasizes the importance of optimizing the synthesis process to achieve materials with high electrochemical activity, stability, and durability. The results of experimental studies on various biomass-derived electrocatalysts, including those from coconut shells, glossy privet fruits, bamboo fungus, tea leaves, and soybean shells, are presented, showing promising performance in ORR applications. The review concludes that biomass-derived electrocatalysts offer a viable alternative to PGM-based catalysts, with the potential to significantly reduce the cost and environmental impact of energy conversion devices.Biomass-derived electrocatalysts for oxygen reduction in energy conversion devices are promising alternatives to platinum group metal (PGM)-based catalysts. These materials are derived from abundant, low-cost, and renewable biomass sources, offering sustainable and cost-effective solutions for applications such as proton exchange membrane fuel cells (PEMFCs), anion exchange membrane fuel cells (AEMFCs), and zinc-air batteries (ZABs). The focus of this review is on the development of PGM-free electrocatalysts with high performance for the oxygen reduction reaction (ORR), which is a critical process in fuel cells and batteries. The review highlights the importance of synthetic methods in determining the properties of these materials, including their specific surface area, porosity, and electrochemical activity. The results show that biomass-derived materials can achieve performance comparable to commercial PGM-free electrocatalysts, although further improvements are needed for practical deployment. The review also discusses the role of heteroatoms such as nitrogen and fluorine in enhancing the electrocatalytic activity of biomass-derived materials. Various synthesis methods, including hydrothermal carbonization, pyrolysis, and chemical activation, are explored for their effectiveness in producing high-performance electrocatalysts. The review emphasizes the importance of optimizing the synthesis process to achieve materials with high electrochemical activity, stability, and durability. The results of experimental studies on various biomass-derived electrocatalysts, including those from coconut shells, glossy privet fruits, bamboo fungus, tea leaves, and soybean shells, are presented, showing promising performance in ORR applications. The review concludes that biomass-derived electrocatalysts offer a viable alternative to PGM-based catalysts, with the potential to significantly reduce the cost and environmental impact of energy conversion devices.