Anammox　is　a　highly　efficient,　environmentally　friendly,　and　promising　form　of　biological　denitrification.　Since　nitrite　is　not　present　in　the　majority　of　wastewater,　the　lack　of　electron　acceptors　(nitrite)　greatly　limits　the　practical　application　of　Anammox.　However,　many　researchers　have　overlooked　the　option　of　employing　other　electron　acceptors.　Much　evidence　suggests　that　Anammox　is　an　electroactive　microorganism　that　can　deliver　electrons　to　various　extracellular　electron　acceptors.　This　information　informs　researchers　that　Anammox　cells　are　not　limited　to　accepting　electrons　only　from　electron　acceptors　within　their　interior.　It　also　provides　the　possibility　that　Anammox　bacteria　can　utilize　other　electron　acceptors.　Many　studies　have　shown　the　possibility　that　Anammox　bacteria　can　use　other　electron　acceptors.　However,　the　implementation　of　the　Anammox　process　for　various　electron　acceptors　faces　some　challenges　in　actual　applications.　We　review　several　electron　acceptors　(nitrite,　nitric　oxide,　ferric　iron,　sulfate,　and　electrode)　that　have　been　shown　to　be　utilized　by　Anammox　as　electron　acceptors.　This　paper　provides　a　comprehensive　review　of　the　physicochemical　properties　of　these　electron　acceptors,　elucidates　the　intricate　transformation　pathways　of　ammonia　nitrogen　catalyzed　by　distinct　electron　acceptors,　and　highlights　the　pivotal　role　of　Anammox　bacteria　in　the　nitrogen　cycle.　The　electron　transfer　theory　is　used　to　explain　the　reasons　for　the　Anammox　nitrogen　removal　efficiency　differences　under　different　electron　acceptors.　It　also　discusses　Anammox＇s　extracellular　and　intracellular　electron　transfer　mechanisms　in　the　presence　of　several　electron　acceptor　types.　The　aim　is　to　enhance　researchers＇　understanding　of　the　metabolic　variety　of　Anammox　bacteria　and　to　realize　a　practical　application.　Thus,　the　study＇s　information　gaps,　shortcomings　of　different　electron　acceptors　Anammox　process,　and　the　required　further　improvements　are　all　identified　and　discussed.　©　2023　Elsevier　B.V.