A　lab-scale　ceramic　membrane　bioreactor　(MBR)　with　active　membrane-fouling　control　system　was　developed　for　the　partial　nitrification　(PN)　process.　The　in　situ　membrane　cleaning　method　was　applied　to　remove　the　contaminants　on　the　surface　of　the　membrane　with　no　interruption　of　the　wastewater　treatment.　The　results　showed　that　the　device　increased　critical　flux　and　reduced　gel　layer　resistance　(Rg)　and　internal　resistance　(Ri)　of　the　flat-sheet　ceramic　membrane　by　inhibiting　the　formation　of　the　cake　layer.　In　long-term　experiments,　nitrite　oxidizing　bacteria　(NOB)　was　successfully　suppressed,　and　nitrite　accumulation　rate　(NAR)　was　achieved　at　a　high　level,　up　to　90.09%;　the　effluent　NO2−-N/NH4+-N　was　maintained　in　balance　dynamically　with　an　average　ratio　of　~1.30,　which　would　be　beneficial　to　the　proliferation　of　Anammox　bacteria　and　the　following　autotrophic　nitrogen　removal　(ANR)　process.　Moreover,　with　the　assistance　of　in　situ　cleaning,　energy　input　from　aeration　was　significantly　reduced,　while　over　aeration　was　avoided　for　more　stable　PN　performance.　©　2023　by　the　authors.