Denitrifying anaerobic methane oxidation (DAMO) is a novel denitrification process with methane as the electron donor and NO₃^-/NO₂^- as the electron acceptor under anaerobic condition. As a greenhouse gas, CH₄ has 20-30 times greater global warming potential than CO₂. CH₄, instead of conventional carbon source, is used for denitrification in the process of DAMO, which is beneficial for reducing global warming effect and improving nitrogen cycle. It has been found that Candidatus Methylomirabilis oxyfera (belonging to bacteria) and Candidatus Methanoperedens nitroreducens (archaea) are the two main microbial communities participating in DAMO process. The former conducts NO₂^-DAMO process via “intraaerobic pathway” while the other uses “reverse methanogenesis pathway” to couple NO₃^- reduction with methane anaerobic oxidation. This paper elaborated the intracellular metabolic pathway of M. oxyfera and M. nitroreducens, and summarized the influence factors of DAMO process in detail, including substrate (CH₄ and NO₂^-/NO₃^-) concentration, reactor configuration and temperature, etc. Meanwhile, the current status of DAMO application on nitrogen removal was also investigated. With further exploration of the mechanisms, enrichment and influence factors of microbial communities, the propulsion of DAMO industrial application would be the frontier in the future.