The results of impeller aero-design are presented based on fluid flow calculation of the impeller with prescribed swirl distribution along meridional streamlines.Swirl distribution is controlled in accordance with Bezier curve for three distinctive load formulas.The designed impellers are compared with themselves to show their performances by applying Numeca software.Results show that aft-loaded blade is of priority.Swirl distribution on Bezier line can be controlled flexibly in design process.