Membrane fouling in the membrane bioreactor (MBR) is typically caused by the interaction of microbial characteristics, hydrodynamic behavior, operation environment, wastewater characteristics and membrane properties, which result in the deterioration of performance and increasing energy consumption and cost of membrane replacement. The effect of the crucial MBR parameters (the microbial loading and characteristics, dissolved oxygen (DO), hydraulic retention time (HRT), backwashing conditions and membrane characteristics) on membrane fouling was investigated in a submerged membrane bioreactor (SMBR) during the long term treatment of synthetic coke wastewater. Also the optimum operation strategies were further utilized in order to satisfy the minimal membrane fouling operation through a long-term evaluation of the MBR performance. It has been demonstrated that with application of these optimal designed conditions, significant membrane fouling improvements were achieved over a long operating time, so it was possible to perform in sustainable operation for MBR. In this study, the upper limit of the sustainable flux is found to be as much as 18.6 L/m(2) h and the optimum sustainable flux value should be 50 approximately 75% of critical flux to satisfy the desired sustainable operation period.