The present invention relates to a a closure system for containers comprising a closing element (1) integrally sealable to the container (10) at one of its openings (3) to be closed, and a preferential separation zone (11) between said container (10) and said closing element (1), said closure system (C) being characterized in comprising first guiding and/or coupling means (A, 12, 13) for guiding and controlling the movement of the closing element (1) from a first blocking position, wherein the closing element (1) is integral to the container (10), to a second unblocking position, wherein the closing element (1) is apart from the container (10) in correspondence of the preferential separation zone (11) having, as guide means for opening, a first thread (13) on the insert (12) and a second thread (4) formed within the closing element (1).