A　pilot-scale　anaerobic/anoxic/aerobic-membrane　bioreactor　was　utilized　to　treat　wastewater　from　the　primary　sedimentation　tank　in　a　municipal　wastewater　treatment　plant　in　Beijing.　After　about　200　days　of　experimental　study,　it　shows　good　removal　efficiency　of　chemical　oxygen　demand　(COD),　biological　oxygen　demand　(BOD),　and　total　organic　carbon　(TOC),　which　reaches　stably　92%,　98%,　and　85%,　respectively　at　the　hydraulic　retention　time　(HRT)　of　12.5　h.　Contribution　of　COD　removal　by　biodegradation　and　microfiltration　is　89%　and　11%,　respectively.　The　removal　efficiency　of　NH4+-N,　and　total　nitrogen　(TN)　is　about　98%,　85%,　with　on　average　ρ(TN)　of　permeate　10　mg/L.　The　removal　efficiency　of　TP　is　about　85%,　with　ρ(TP)　of　permeate　about　0.93　mg/L　at　the　sludge　age　of　40　days.　The　proportions　of　TP　removal　by　denitrifying　phosphorus　removal,　the　aerobic　phosphorus　uptake,　and　membrane　cut-off　is　44.6%,　51.8%,　3.6%,　respectively.　The　permeation　of　extreme　low　turbidity　and　almost　non-SS　can　be　reclaimed　for　the　urban　miscellaneous　water　consumption.　Intermittent　suction,　scouring　aeration,　on-line　hydraulic　backwash,　and　regular　drug-wash　as　a　mean　of　inhibiting　membrane　fouling,　ensures　the　sustainable　running　of　the　whole　system.