Because of the shortage of the current method of evaluating the performance of the middleman,the paper presents a new method of evaluating the performance of the middleman,which is based on BP neural network.Firstly,it sets up an index system.to evaluate the performance of the middleman,and then designs the BP neural network model according the index system,and presents the workable evaluating procedure.On the method of computation,the Neura Network Toolbox(NNT)based on Matlab is used to make network design and compute.Through the training and test of lots of study samples,the error of the model is limited to a preliminary range.Finally,the model has been used in Jiangsu power machinery Ltd.And also some features and suitability of the model in evaluation of the performance of the middleman are discussed.