The invention concerns a system for realizing complex constructions, characterized in that it comprises a plurality of basic elements, and a plurality of constructive and/or figurative elements, that can be coupled with said basic elements, each basic element being comprised of ferromagnetic material, to be coupled with a first type of constructive and/or figurative magnetic elements, said basic elements being further provided with not-magnetic coupling means, for coupling with at least a second type of plastic material elements, said plastic material elements being provided with coupling means corresponding to the coupling means provided on said plurality of basic elements.