In order to improve the prediction accuracy of grey GM(1,1) model and the mapping ability of BP neural network, an improved prediction model of grey BP neural network is proposed. Two models, including grey system theory and BP neural network, were improved respectively, and then a new prediction model was combined in series. Carry out the simulation by test data. The results show that the improved model has the advantages of both methods, the prediction accuracy is highly improved, the relative error is reduced, and the operation speed is faster.