A novel integrated vertical membrane bioreactor (IVMBR) composed of both anoxic and oxic zones based on the installation of a three-phase separator was developed to simultaneously remove organic matter and nitrogen. The three-phase separator could successfully create favorable conditions for both denitrifying and nitrifying process, which occurred in upper part.(anoxic zone) and lower part (oxic zone) of the reactor, respectively. A lab-scale IVMBR was operated in parallel with a controlled MBR (without the three-phase separator), and their performance on the removal of organics and nitrogen was compared. The results show that both IVMBR and controlled MBR were efficient in removal of COD and NH4+-N when fed with synthetic wastewater or domestic sewage. IVMBR performed a better removal performance of NH4+-N and TN when the volume ratio of anoxic zone and oxic zone and internal recycle rate were around 1% and 400%, respectively. However, the TN removal performance of controlled MBR was quite poor due to the lack of anoxic condition. Additionally, it was found that IVMBR could save half of alkalinity compared to the controlled one. Overall, the IVMBR has the potential of being applied in the treatment of domestic sewage and ammonium industrial wastewater. (C) 2013 Elsevier B.V. All rights reserved.