The invention discloses an elliptic-curved-surface rotary wheel of an inclined impact type water turbine. The elliptic-curved-surface rotary wheel comprises a circular disc and a plurality of wheel blades, wherein a shaft hole is formed in the center of the circular disc; a shaft is connected with a power generator through the shaft hole; the diameter of the shaft hole is determined by the power generator; the root parts of the wheel blades are fixedly arranged at the periphery of the circular disc by welding; each wheel blade is defined by a half of elliptic spherical surface which is not closed, and one side of the corresponding wheel blade is cut by a quarter of the whole elliptic spherical surface, and the cutting surface faces outwards when the wheel blade is fixed. The inclined impact type water turbine is connected with the power generator; when the water jet flow impacts the wheel blades, the wheel blades drive the rotary wheel and the shaft to rotate together, so that water energy is converted into electric energy through the power generator. The elliptic-curved-surface rotary wheel can be used in a high-water-head small-flow water energy conversion power-generating system, so that conversion efficiency of water energy is improved.