Abstract: With the continuous depletion of fossil fuel reserves and the increasingly serious environmental pollution issues, the development and utilization of renewable energy have become one of the important directions of global energy policies. Biomass, as a rich and renewable resource, is of crucial importance. Biomass can be converted into three main products, namely pyrolysis gas, bio-oil, and biochar, through the pyrolysis process according to demand. into three main products, namely pyrolysis gas, bio-oil, and biochar, through the pyrolysis process according to demand. Therefore, biomass pyrolysis has great potential and prospects. Based on this research, this paper reviews the key pyrolysis processing parameters that affect the products of biomass pyrolysis, especially reaction temperature, heating rate, residence time, and reaction atmosphere. In the pyrolysis process, biomass first undergoes initial volatile decomposition, followed by carbonization, and finally secondary carbonization and tar cracking. Increasing temperatures promote more cracking and gasification reactions, leading to higher yields of bio-oil and gas, while the yield of biochar decreases. Rapid heating tends to produce more gaseous and liquid bio-oil, whereas slow heating favors the generation of biochar, enhancing its chemical stability and porosity. Increased residence time promotes secondary reactions, altering the chemical composition of bio-oil. Under different atmospheric conditions, such as N₂ or CO₂, the excessive oxidation of biomass can be suppressed, or dehydrogenation and decarboxylation reactions can be facilitated, resulting in changes to the composition of pyrolysis gas and bio-oil, as well as the properties of biochar. By precisely controlling these parameters, the pyrolysis process of biomass can be optimized to achieve ideal three-phase products. Research results indicate that adjusting pyrolysis parameters can effectively improve the yield and properties of pyrolysis products, thereby enhancing the economic viability and environmental friendliness of biomass pyrolysis. Finally, addressing the difficulties and challenges faced in the development of biomass pyrolysis technology in the energy and environmental fields, a future direction for the development of carbon capture technology is proposed, emphasizing the integration of biomass pyrolysis technology with other renewable energy technologies. Biomass pyrolysis will focus on developing new catalysts with high catalytic efficiency, stability, and cost-effectiveness.