Removing　nitrogen　and　phosphorus　from　low　ratio　of　chemical　oxygen　demand　to　total　nitrogen　and　temperature　municipal　wastewater　stays　a　challenge.　In　this　study,　a　pilot-scale　anaerobic/aerobic/anoxic　sequencing　batch　reactor　(A/O/A-SBR)　system　first　treated　15　m3/d　actual　municipal　wastewater　at　8.1–26.4　°C　for　224　days.　At　the　temperature　of　15.7　°C,　total　nitrogen　in　influent　and　effluent　were　45.5　and　10.9　mg/L,　and　phosphorus　in　influent　and　effluent　were　3.9　and　0.1　mg/L.　16　s　RNA　sequencing　results　showed　the　relative　abundance　of　Competibacter　and　Tetrasphaera　raised　to　1.25　%　and　1.52　%.　The　strategy　of　excessive,　no　and　normal　sludge　discharge　enriched　and　balanced　the　functional　bacteria,　achieving　an　endogenous　denitrification　ratio　more　than　43.3　%.　Sludge　reduction　and　short　aerobic　time　were　beneficial　to　energy　saving　contrast　with　a　Beijing　municipal　wastewater　treatment.　This　study　has　significant　implications　for　the　practical　application　of　the　AOA-SBR　process.　©　2024　Elsevier　Ltd