Abstract: Chemical looping gasification is an innovative energy conversion technology with significant research and application value. With the growing demand for clean energy in recent years, in-depth investigations on this technology are increasingly carried out in the fields of biomass and coal gasification. To explore the reaction mechanism and process of lignin chemical looping gasification under the action of iron-based oxygen carriers, the ReaxFF-MD simulation method is adopted to model the lignin chemical looping gasification process with Fe₂O₃ as the oxygen carrier. The results show that Fe₂O₃ not only accelerates the pyrolysis of lignin but also provides lattice oxygen to enhance the cracking and conversion of tar and char. An increase in temperature raises the yields of CO and H₂ and improves the pyrolysis and gasification efficiency of lignin. The elevated molar ratio of oxygen carrier to biomass promotes CO generation and achieves high-yield syngas, with a maximum syngas yield of 47.65% attained at the molar ratio of 2.5 between the two. For investigating the influence of biomass component variation, the chemical looping gasification process of the coexistent system of cellulose and lignin is simulated with Fe₂O₃ as the oxygen carrier. The results demonstrate that a maximum syngas yield of 33.97% is achieved for the system at the molar ratio of cellulose to lignin of 3∶7, and the syngas presents a higher calorific value under this condition. In addition, a performance comparison between spinel NiFe₂O₄ and Fe₂O₃ reveals that NiFe₂O₄ can supply more lattice oxygen for the lignin chemical looping gasification process. This not only increases the hydrogen yield and facilitates the efficient and clean conversion of lignin to syngas but also improves the carbon conversion rate, thus meeting the current target requirements for carbon emission reduction.