In　order　to　promote　practical　engineering　application　of　anaerobic　ammonium　oxidation(anammox)　process,　reduction　of　primary　sludge(PS)　in　wastewater　treatment　plants(WWTPs)　and　removal　of　nitrate　contaminant,　a　single-stage　simultaneous　alkaline　fermentation　coupled　with　partial　denitrification(SAFPD)　system　was　established　successfully　in　this　study.　Nitrite　production　was　rapidly　achieved　from　nitrate　wastewater　with　PS　as　inoculated　sludge　and　fermentable　substrate　under　anaerobic　and　anoxic　operating　conditions.　During　the　stable　operation　period,　the　primary　sludge　reduction(PSR)　and　productivity　of　organic　matters　were　27.9%　and　483.8mgCOD/gVSS,　with　nitrate　removal　of　90.7%,　NO3-　to　NO2-　transformation　ratio(NTR)　of　80.0%.　After　125　days　of　acclimation,　the　relative　abundance　of　Thauera,　Dechloromonas　and　Candidatus_Competibacter　increased　from　0.17%,　0.02%　and　0.05%　to　11.58%,　4.28%　and　5.6%　respectively.　Above　results　showed　that　this　SAFPD　system　not　only　realized　the　reduction　of　PS　and　nitrate　removal,　but　also　laid　a　solid　foundation　for　anammox　process　with　its　high　nitrite　production.