In this research, the structure optimized BP-ANN model was applied to simulate the permeate flux as a function of mixed liquor suspended, temperature, dissolved oxygen, hydraulic retention time, transmembrane pressure and operating time during dead-end microfiltration of activated sludge suspensions and its supernatant from sequencing batch reactor (SBR). This artificial neural network approach was also used to model the chemical oxygen demand (COD) concentration of effluent from SBR. The results showed that the structure optimized single hidden layer neural networks was able to accurately simulate the dynamic behavior of permeate flux and the COD concentration for SBR activated sludge process, and this BP-ANN model possessed higher accuracy than that of C. M. Silva's predictive model and linear multi-regression model. (C) 2011 Elsevier B.V. All rights reserved.