Abstract Anaerobic digestion digestion of garbage is attracting much attention because of its application in waste volume reduction and the recovery of its application in waste volume reduction and the recovery of biogas for use as an energy source.ln this review, various factors influencing the degradation of garbage and the production fo biogas are discussed. The surface hydrophobicity and porosity of supporting materials are important factors in retaining microorganisms such as aceticlastic methanogens and in attaining a higher degradation of garbage and a higher production of biogas. Ammonia concentration,changes in environmental parameters such as temperature and pH, and adaptation of microbial community to ammonia have been related to ammonia mhibition. The effects of drawing electrons from the methanogenic community and donating electrons into the methanogenc community on methane production have been shown in microbial fuel cells and bioelectric helical reactors. The influences of trace elements, phase separation, and co-digestion are also summarized in this review.