Abstract: To determine the number of centrifugal pumps in parallel operation in the design of pressure pumping station for drip irrigation system, the models were developed on the principle of solving the duty point of pumps system operated in parallel to analyze the total flow rate of pumps system varied with the number of centrifugal pumps in parallel operation. It was obtained by the model analysis that the working flow rate of single centrifugal pump decreased with the number of parallel pumps, and the range of diminution decreased also; The total discharge of pumps system increased with the number of parallel pumps, but the range of increment decreased, which decay rate was large than that of single centrifugal pump flow capacity. An example was employed to verify the availability of the models for application. The results can provide a reference for design of pumping station for drip irrigation area.