Abstract: This invention relates to an automatic regulating device for wind-powered propellers having blades which are connected to the propeller hub by torsion springs and are self-adjustable in dependence of the wind forces acting on the blades and returnable by action of the torsion springs. The distinctive feature of the invention is that the torsion spring connecting each blade with the propeller hub has a substantial portion of its length pre-stressed between two abutment points situated on a radius from the propeller axis and radially spaced from each other. The abutment points permit twisting the blade about its longitudinal axis from an initial position by wind forces against action of the prestressed torsion spring. The abutment points are both fixed either in relation to the blade or in relation to the hub.