A　novel　system　coupling　an　up-flow　anaerobic　sludge　blanket　(UASB)　and　sequencing　batch　reactor　(SBR)　was　introduced　to　achieve　advanced　removal　of　organic　and　nitrogen　from　ammonium-rich　landfill　leachate.　UASB　could　remove　88.1%　of　the　influent　COD　at　a　volumetric　loading　rate　of　6.8　kg　COD　.　m(-3).　d(-1).　Nitritationdenitritation　was　responsible　for　removing　99.8%　of　NH4+-N　and　25%　of　total　nitrogen　in　the　SBR　under　alternating　aerobic/　anoxic　modes.　Simultaneous　denitritation　and　methanogenesis　in　the　UASB　enhanced　COD　and　TN　removal,　and　replenished　alkalinity　consumed　in　nitritation.　For　the　activated　sludge　of　SBR,　ammonia　oxidizing　bacteria　were　preponderant　in　nitrifying　population,　indicated　by　fluorescence　in　situ　hybridization　(FISH)　analysis.　The　Monod　equation　is　appropriate　to　describe　the　kinetic　behavior　of　heterotrophic　denitrifying　bacteria,　with　its　kinetic　parameters　determined　from　batch　experiments.　(C)　2015　The　Chemical　Industry　and　Engineering　Society　of　China,　and　Chemical　Industry　Press.　All　rights　reserved.