A　pilot-scale　aerobic　membrane　bioreactor　(MBR)　process　was　operated　to　treat　municipal　wastewater　regarding　on　the　influences　of　biomass　characteristics　on　membrane　permeability　as　well　as　the　membrane　permeability　recovery.　Sucrose　solution　was　added　to　maintain　system　operation　of　a　constant　food　to　microorganisms　(F/M)　ratio　at　0.13　and　a　series　of　physicochemical　and　biochemical　parameters　of　activated　sludge　were　also　measured　throughout　the　whole　trial,　with　correlations　between　biomass　properties　and　membrane　permeability　as　well　as　the　membrane　permeability　recovery　were　further　assessed　by　using　Statistical　Product　and　Service　Solutions　(SPSS)　analyses.　Results　showed　the　mixed　liquor　suspended　solids　(MLSS)　concentration　exerted　the　greatest　influence　on　membrane　permeability　(rp=-0.958,　P=0.000);　soluble　microbial　products　(SMP)　concentration,　soluble　chemical　oxygen　demand　(sCOD)　concentration　and　particle　size　diameter　(PSD)　had　similar　weaker　effects　on　membrane　permeability　(|rp|=0.82~0.85).　Whereas　the　sludge　settleability,　and　filamentous　index　(FI)　had　no　evident　influences　on　membrane　permeability.　The　accumulated　clogged　solids　(ACS)　in　membrane　channels　and　absolute　membrane　permeability　recovery　increased　with　the　increasing　MLSS　concentrations,　implying　that　the　MLSS　concentration　had　direct　effects　on　membrane　clogging　propensity　and　further　proved　that　membrane　clogging　being　another　important　factor　affecting　the　membrane　permeability　except　for　membrane　fouling.　The　off-line　declogging　combined　with　enhanced　chemically　backflushing　(CEB)　could　ensure　the　sustainable　membrane　permeability　recovery　under　the　condition　of　low-flux　[5~6　L/(m2·h)]　operation　at　high　MLSS　concentrations.　©,　2015,　Chinese　Society　for　Environmental　Sciences.　All　right　reserved.