Abstract: A fluid dosing valve assembly for dispensing a volumetric amount of a fluid in precise and repeatable amounts, particularly for dosing small amounts. The fluid dosing valve assembly includes a valve body with a fluid path, and a stem element for opening and closing the fluid path by rotation, the rotation being performed from a first closing position to an opening position and from the opening position to a second closing position, with rotation angles between the first closing position and the opening position and between the opening position and the second closing position that allow the opening cycle to be performed at constant rotational speed.