<p>An impeller (3) of an open-type water pump, comprising a shaft (31) located at the center and multiple vanes (32) extending in the axial direction and evenly distributed in the circumferential direction on the circumferential surface of the shaft (31). The vanes (32) are divided into upper sections (321) and lower sections (322) in the axial direction. At least the bottom parts of the lower sections (322) of the vanes (32) are gradually smoothed and curved in the direction of rotation of the impeller on the circumferential surface of the shaft (31). The range of the height ratio of the height of the lower sections (322) of the vanes (32) to the height of the upper sections (321) is 1-5. By providing the upper sections and lower sections of the vanes with an appropriate height ratio, the impeller is allowed to draw water at a relatively low water level, is not prone to drawing into the impeller foams formed by a washing liquid or food debris on the water surface and thus affecting drawing of water, and allows a sufficient flow to be drawn at a water inlet.</p>
