Method and system for optimizing deep neural network

The invention discloses a method and a system for optimizing a deep neural network. The method comprises the steps of acquiring training data; training the deep neural network according to the training data to obtain weight parameter matrixes among the layers of the deep neural network; determining at least one weight parameter matrix to be optimized from a set of the weight parameter matrixes between every two adjacent layers of the deep neural network; optimizing the weight parameter matrixes to be optimized and decreasing the number of the weight parameters in the weight parameter matrixes to be optimized. With the adoption of the method and system, the redundancy of model parameters can be obviously removed, and the number of effective model parameters can be decreased; the optimized deep neural network can be applied to a voice recognizing system to further obviously reduce the operation burden of calculating posterior probability of deep neural network output in recognizing decoding, and therefore, a deep neural network model can be obviously rapidly recognized and decoded.