An　up-flow　anaerobic　sludge　blanket　reactor　(UASB),　anoxic/oxic　(A/O)-anaerobic　ammonia　oxidation　reactor　(ANAOR　or　anammox　reactor),　and　anaerobic　sequencing　batch　reactor　(ASBR)　were　employed　in　the　treatment　of　landfill　leachate　with　partial　nitrification-anammox　and　half-denitrification-anammox.　The　Chemical　Oxygen　Demand　(COD)　concentration,　ammonium　nitrogen　(NH4+-N)　concentration,　and　total　nitrogen　(TN)　concentration　of　the　basal　leachate　was　2200-2500　mg/L,　1200-1300　mg/L,　and　1300-1400　mg/L,　respectively.　After　a　1:2　dilution　using　domestic　sewage,　the　COD,　NH4+-N,　and　TN　concentrations　in　the　influent　were　800-1000　mg/L,　400-430　mg/L,　and　420-440　mg/L,　respectively.　After　treatment,　the　final　COD,　NH4+-N,　and　TN　were　decreased　to　90-100　mg/L,　13-14　mg/L,　and　35-38　mg/L,　respectively.　In　the　ASBR,　organic　carbon　sources　in　sewage-diluted　landfill　leachate　were　introduced　for　the　conversion　of　nitrate　nitrogen　(NO3--N)　into　nitrite　nitrogen　(NO2--N).　This　enabled　the　continued　reaction　of　NO2--N　with　NH4+-N　from　the　newly　introduced　sewage-diluted　landfill　leachate　via　anammox.　As　a　result,　complete　TN　removal　was　achieved　in　the　system.　Microbial　diversity　analysis　indicated　that　the　relative　abundance　of　ammonia-oxidizing　bacteria　(AOB)　was　four　to　five　times　greater　than　nitrite-oxidizing　bacteria　(NOB)　in　the　A/O　reactor,　showing　that　partial　nitrification　was　prevalent.　The　relative　abundance　of　the　anammox　bacterium　Candidatus　Kuenenia　gradually　increased　in　each　reactor,　reaching　a　maximum　of　1.17%-1.39%.　Using　this　set-up,　we　achieved　advanced,　efficient,　and　economical,　COD　reduction　and　nitrogen　removal.　Taken　together,　the　findings　provide　important　insights　into　the　optimal　operation　of　landfill　leachate　treatments.