Disclosed is a centrifugal pump flow prediction method based on measurement of power and differential pressure. The centrifugal pump flow prediction method is characterized by including steps that 1, a whole centrifugal pump is respectively divided into a motor module, a mechanical model and a hydraulic power module on the basis of a 'gray box' construction theory; 2, a whole flow prediction mathematical model of the centrifugal pump is built on the basis of system analysis; 3, local establishment of a motor output power prediction mathematical model is performed on the basis of a motor inner loss model; 4, local establishment of a mechanical transmission part output power (or centrifugal pump input power) prediction mathematical model is performed on the basis of a mechanical loss model; 5, local establishment of a model among centrifugal pump input power, flow and rotating speed and a model among centrifugal pump differential pressure, flow and rotating speed is performed on the basis of a fluid flow loss model; 6, a centrifugal pump flow prediction model based on power (rotating speed and torque) and differential pressure is established by combination with a motor mathematical model, a mechanical mathematical model and a hydraulic power mathematical model; 7, the centrifugal pump flow prediction model is corrected by means of a compensation algorithm, and the flow prediction accuracy is improved.