The　long-term　stability　of　nitrogen　removal　from　municipal　landfill　with　high　ammonia　nitrogen　(NH4+-N)　content　was　investigated　by　using　a　biological　system　consisting　of　a　first-stage　up-flow　anaerobic　sludge　bed　(UASB)　and　sequencing　batch　reactor　(SBR)　under　normal　and　low　temperature　conditions.　The　623　days　experimental　results　clearly　showed:　the　efficient　denitrification　and　methanogenesis　were　conducted　in　a　same　UASB　reactor,　and　almost　100%　of　denitrification　was　obtained,　when　feed　COD　concentration　ranged　from　1000　mg·L-1　to　13800　mg·L-1,　effluent　COD　concentration　was　between　150　mg·L-1　and　1234　mg·L-1,　and　when　the　influent　ammonia　nitrogen　(NH4+-N)　changed　from　574　mg·L-1　to　2360　mg·L-1,　the　effluent　NH4+-N　was　below　10　mg·L-1,　the　removal　efficiency　reached　90%　and　98%,　respectively.　Especially,　above　99.2%　removal　efficiency　of　TN　was　obtained,　and　effluent　TN　concentration　was　below　30　mg·L-1,　advanced　and　efficient　nitrogen　and　organic　removal　were　achieved　in　the　biological　system.　Furthermore,　stable　nitrification　and　denitrification　were　achieved　during　the　entire　experiment　period,　especially,　were　maintained　successfully　for　171　days　at　the　temperature　below　15°C　and　the　lowest　temperature　of　10.2°C　during　two　winters.