The present invention provides a processing system for a binary weight convolutional neural network. The system comprises: at least one storage unit for storing data and instructions; at least one control unit for acquiring the instructions stored in the storage unit and sending out a control signal; and, at least one calculation unit for acquiring, from the storage unit, node values of a layer in a convolutional neural network and corresponding binary weight value data and obtaining node values of a next layer by performing addition and subtraction operations. With the system of the present invention, the data bit width during the calculation process of a convolutional neural network is reduced, the convolutional operation speed is improved, and the storage capacity and operational energy consumption are reduced.