A submersible active support structure for turbine towers and substations or similar elements, in offshore facilities, which is made up of hollow concrete bodies joined together by means of segments or beams, through which water passes from one body to another, with a pumping system that regulates the inclination of the structure based on the overturning moment, equipped with means for regulating immersion, which regulate the amount of water in the hollow bodies such that, in its working position, the center of gravity of the structure is below the center of buoyancy thereof, and the area of the cross-section of the structure at the waterline is smaller than the sum of the submerged cross-sections of said hollow bodies. In addition, the assembly may operate with a traditional mooring system.