A　sequencing　batch　reactor　(SBR)　was　used　to　treat　real　domestic　wastewater　focusing　on　the　achievement,　maintenance　and　the　feasibility　of　nitrite　accumulation　under　real-time　control.　Keeping　temperature,　MLSS　and　dissolved　oxygen　(DO)　in　reactor　at　28　+/-　1　degrees　C,　2,400　mg/L　and　higher　than　2.0　mg/L　respectively,　shortcut　nitrification-denitrification　was　successfully　achieved　after　about　two　months.　But　the　sudden　raise　of　ammonia　loading　rate　(ALR)　caused　deterioration　of　nitrite　accumulation　and　occurrence　of　filamentous　sludge　bulking.　These　undesirable　situations　could　be　solved　by　pre-anaerobic　operation　mode.　If　applying　long-term　real-time　control　strategy　to　supervise　the　nitrification　course,　the　sludge　population　optimization　and　high　nitrite　accumulation　rate　at　different　DO　levels　could　be　achieved.　The　strategy　taking　pH　and　aeration　quantity　as　control　parameters　for　nitrification　in　SBR　was　put　forward　under　invariable　DO　conditions　in　this　paper.　By　maintaining　low　DO　level　(below　1.0　mg/L),　the　shortcut　nitrification-denitrification　could　be　achieved　in　the　same　reactor　with　simultaneous　nitrification　and　denitrification　(SND),　through　which　the　removed　nitrogen　accounted　for　49.12%　to　66.81%　of　total　nitrogen　(TN)　in　influent　at　the　end　of　shortcut　nitrification.