Abstract: In order to avoid the energy loss caused by traditional frequency constant speed motor, applying the frequency control technique to pump unit can meet the requirement of pipeline operation at low transportation capacity and reach the aim of energy saving. The paper describes the principle of frequency control in detail. Taking the actual oil product pipeline as an example, SPS simulation software is employed to simulate the working condition of fxed speed pump and variable speed pump which uses frequency control technique under different transportation capacity. The energy saving effect before and after installation of frequency control device is compared, and furthermore the economic beneft brought by application of frequency control technique to oil pump is evaluated. It is pointed out that the accuracy of simulation results will be lowered if the accurate throttle valve curve and the characteristic curve of pump under multiple rotating speed are absent in the input parameters.