Advanced　nitrogen　removal　had　been　realized　from　mature　landfill　leachate　via　three-stage　anaerobic　ammonium　oxidation　(Anammox)　system　during　the　previous　study.　However,　the　Anammox　system　was　influenced　by　factors　such　as　influent　nitrite　and　organic　concentrations　and　needed　to　be　optimized.　To　optimize　the　Anammox　system,　this　study　investigated　Anammox　Sequence　Batch　Reactor　(ASBR)　with　different　feeding　modes　and　influent　organic　concentrations.　The　results　showed　that　with　influent　ammonia　and　nitrite　concentrations　of　250　+/-　20　and　320　+/-　20　mg/L,　respectively,　a　continuous　feeding　mode　reduced　the　adverse　effect　of　high　influent　nitrite　concentration　on　Anammox.　A　small　amount　of　organics　improved　rather　than　inhibited　nitrogen　removal.　However,　as　influent　COD　increased　(from　600　+/-　50　to　800　+/-　50　mg/L),　Anammox　was　gradually　inhibited.　Influent　organics　concentration　should　be　kept　below　800　mg/L,　which　facilitated　Anammox.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.