In order to investigate the effect of rotational speed on the hydraulic performance of inlet and outlet conduits for S-shaped shaft extension tubular pumping system, three dimensional and steady turbulent flow in the pumping system was simulated by the computational fluid dynamics technology. Then, the CFD results are compared with the experiment results to validate the application of numerical analysis. The hydraulic performance parameters of inlet and outlet conduits were quantitatively analyzed considering the hydraulic interaction of conduits and impeller. Results indicated that the change trend of relationship curves between hydraulic loss ratio and flow rate coefficient is same in different rotational speed. With the increase of flow rate coefficient, the hydraulic loss ratio gradually increases, the hydraulic efficiency increases firstly then decreases gradually, and the average velocity circulation of outlet section firstly increases then decreases gradually under the same rotational speed. Meanwhile, with the increase of rotational speed, the average velocity circulation gradually increases under the same flow rate coefficient. In addition, the relative swirl angle decreases firstly, then increases with the increase of flow rate coefficient under different rotational speed. It could also be concluded that with the increase of rotational speed, the static pressure ratio of outlet conduit increases gradually and the distribution of drift angle in inlet section of outlet conduit is same. There is no linear functional relationship between square of hydraulic loss and flow rate for outlet conduit.