Abstract: On the basis of analyses of hydraulic losses, volume losses and machinery losses of impellers and volutes of double-channel pumps, the performance prediction methods of the head curve and efficiency curve of double-channel pump were provided. The calculation methods of friction losses, diffuser losses and main local hydraulic losses of impellers and volutes of double-channel pumps were given. The examples of performance prediction show the performance prediction methods provided by this paper have a high precision.