Abstract: A device for compensating length variations of tensioned cables, with a substantially constant tension, including a contrast element, which is meant to be interposed between one end of the tensioned cable and an anchoring element and is adapted to generate an elastic reaction which can vary as a function of the length variation of the cable. The device includes elements for connecting the contrast element to the cable which are suitable to convert the elastic reaction of the contrast element into a substantially constant tension applied to the cable, regardless of its length, over a preset length variation range.