Abstract: Based on the composition characteristics, hazards and treatment methods of biomass tar, the mechanism of catalytic cracking of biomass tar and the research progress in recent years are briefly introduced, and the catalytic conversion mechanism of biomass charcoal (mainly involving cracking, The three reactions of reforming and condensation), the adsorption and reforming of biomass charcoal, and the catalytic conversion process, the catalytic performance of biomass charcoal is affected by factors such as raw materials, cracking temperature, heating rate and residence time. By analyzing the performance changes of biomass charcoal after modification, it is found that the addition of metal promoters or structural modification of biomass charcoal has the potential for high-efficiency catalytic cracking of tar, which provides a direction for further research and development of low-cost composite catalysts.