The membrane module is placed in the reactor, and the filtering liquid is obtained by vacuum pumping or natural siphoning. The cross-flow required for cleaning the membrane is generated by air agitation. Air is added directly below the membrane. The liquid shear force reduces the sedimentation of material on the surface of the membrane, thereby reducing the pollution of the membrane. Integrated membrane bioreactor, the process is a combination of conventional sewage biodegradation technology and membrane separation filtration technology. After the organic sewage is biodegraded, the solid-liquid separation of the sewage is completed by using a microfiltration membrane or an ultrafiltration membrane to achieve purification of the sewage. The function of the membrane module here is to replace the secondary sedimentation tank and sedimentation filtration unit in the conventional sewage treatment process so that the hydraulic retention time and the sludge age are no longer related, and the stability of the affluent and the excellent water quality can be guaranteed. The integrated type has a small footprint and low energy consumption and can be modularly constructed into a series of sewage treatment stations or sewage treatment plants.