Hydrodynamics characteristics like flow pattern, shear rate distribution, power consumption, axial pumping capacity, mixing time, and mixing efficiency of an ellipse gate (EG) impeller were investigated by experimental and numerical methods. The numerical simulation results were validated by experimental data of power consumption and mixing time. Results indicate that the axial pumping number of the EG impeller is larger than that of any other reported large-scale impeller under laminar regime, and that the shear rate formed by this impeller is less sensitive to Reynolds numbers. In-depth analysis reveals the different function of each part of the EG impeller under different flow regimes. This impeller provides an almost similar mixing efficiency like the double-helical ribbon impeller under laminar regime, but much higher mixing efficiency both under transitional and turbulent flow regimes.