A submerged polyvinyl chloride（PVC）membrane bioreactor (MBR) （PVC-MBR）was used to treat municipal wastewater. The long-term performance, operational state and membrane cleaning of the novel PVC-MBR was investigated systematically. The MBR showed better removals of the main pollutants, such as COD , NH4+-N, T-P and turbidity. The removal efficiencies for COD and NH4+-N were above 90%, and 95%, respectively. The average T-P effluent concentration  was less than 0.5 mg/L when chemical coagulation was used in the process. The turbidity of membrane permeate was less than 0.1 NTU. The MBR permeate could meet Chinese reuse standard (GB/T 18920－2002). The membrane system was stable as the TMP was less than -35 KPa at the flux of 20 L/(m2.h). Chemical cleaning was adopted by 1000ppm NaClO mixed with 0.2% NaOH after operating 195 days , and the results showed that TMP conditions of MBR system was recovered to the level of the new one after the cleaning.