In this study, a novel membrane bioreactor (MBR) in which nitrification and denitrification simultaneously proceed in a single reaction chamber is proposed for advanced municipal wastewater treatment. Anoxic/aerobic conditions are separately created in the proposed MBR by inserting baffles inside of the membrane chamber and consequently simultaneous nitrification/denitrification can be carried out The technology established in this study can easily be applied to almost all of existing MBRs. Pilot-scale experiment to examine performance of the proposed MBR was carried out at an existing municipal wastewater treatment plant In this paper, experimental results obtained in the pilot study are shown. Inserting baffles inside the membrane chamber actually increased removal of nitrogen by 30%. Coagulation and sedimentation were carried out in the pilot study for pre-treatment of the MBR. Removal efficiency in terms of total organic carbon, total phosphorus, and total nitrogen determined for whole treatment system (i. e., coagulation/sedimentation/the proposed MBR) was attained to 91.5%, 97.2%, and 66.2%, respectively. Increase in transmembrane pressure difference was minimal in the pilot operation. It was demonstrated that high quality effluent and mitigation of membrane fouling could simultaneously be achieved by the proposed MBR.