A matrix-multiplying-vector operation method and a processing device for performing the same are provided. The matrix-multiplying-vector method includes distributing, by a main processing circuit, basic data blocks of the matrix and broadcasting the vector to a plurality of the basic processing circuits. That way, the basic processing circuits can perform inner-product operations between the basic data blocks and the broadcasted vector in parallel. The results are then provided back to main processing circuit for combining. The technical solutions proposed by the present disclosure provide short operation time and low energy consumption.