Abstract: An electromagnetic actuator for door units and the like, particularly for up-and-over doors, which includes a tubular guide having at least two side-by-side rectilinear portions, a flexible rack housed partly within one rectilinear portion of the guide and partly within the other, such that it can undergo axial sliding, a geared motor unit provided with a gearwheel engaging the flexible rack via an aperture, provided in at least one of the two rectilinear portions of the tubular guide, one hanger fixed to the flexible rack, and members for mechanically connecting the hanger appendix to the door unit or the like to be moved.