The study explores the use of biogas as a gasification agent to convert fermented bio-digested residues into hydrogen-rich syngas. Results show that the H2/CO ratio in biogas gasification is significantly higher than CO2 gasification, with CH4 and CO2 synergistically enhancing hydrogen production. The comprehensive pyrolysis index in a biogas atmosphere indicates thorough gasification of bio-digested residues, validating the effectiveness of hydrogen migration during gasification. By identifying key reaction pathways, the study offers insights into advancing biomass energy utilization and optimizing syngas production processes. This research demonstrates the potential of biogas-driven gasification systems for clean and efficient hydrogen production from bio-digested residues.