Abstract:In activated sludge sewage treatment process, the water will change dramatically, and run strongly coupled, nonlinear, big lag, the establishment of the BP neural network model simulation, using trial and error method to determine the number of hidden layer nodes, avoiding the establishment of too large network. In the process of training the network, the establishment of an appropriate network model to avoid excessive training. Through the input data of water quality in the sewage treatment process of variable parameters, to predict the future output of a water quality in a certain time variable parameters.The results show that, BP neural network can be applied to the activated sludge treatment process simulation and prediction of water quality parameters.