A locking device for laces, shoelaces, cords and the like, particularly adapted to close shoes, rucksacks, items of clothing and the like, wherein the locking device comprises - a base, which is adapted to be fixed to the product provided with the lace to be locked and is provided with at least one seat for the passage of a lace to be locked, - a lever, which has at least one element for pinching said lace in said at least one passage seat, and at least one guiding seat (16a, 16b, 17a, 17b) for said lace, said lever being connected to said base, proximate to said at least one passage seat, by pivoting means which define for it a rotation axis, around which said lever is able to rotate with respect to said base in order to pass reversibly - from an open configuration, in which said at least one passage seat is free from said at least one pinching element, said lace passing through and being able to slide freely within said at least one passage seat, - to a closure configuration, in which said lever is folded down onto said base, said at least one pinching element engaging said at least one passage seat so as to pinch thereat said lace in order to prevent sliding in said at least one passage seat, an end portion of said lace passing through said at least one guiding seat (16a, 16b, 17a, 17b) to be directed in a preselected reverse direction, which is defined by said at least one guiding seat (16a, 16b, 17a, 17b), - and vice versa characterized in that said at least one guiding seat (16a, 16b, 17a, 17b) comprises at least one second guiding seat 17a, 17b), which is open so as to pass through a second end of said lever, which is opposite with respect to a first end. - a base, which is adapted to be fixed to the product provided with the lace to be locked and is provided with at least one seat for the passage of a lace to be locked, - a lever, which has at least one element for pinching said lace in said at least one passage seat, and at least one guiding seat (16a, 16b, 17a, 17b) for said lace, said lever being connected to said base, proximate to said at least one passage seat, by pivoting means which define for it a rotation axis, around which said lever is able to rotate with respect to said base in order to pass reversibly - from an open configuration, in which said at least one passage seat is free from said at least one pinching element, said lace passing through and being able to slide freely within said at least one passage seat, - to a closure configuration, in which said lever is folded down onto said base, said at least one pinching element engaging said at least one passage seat so as to pinch thereat said lace in order to prevent sliding in said at least one passage seat, an end portion of said lace passing through said at least one guiding seat (16a, 16b, 17a, 17b) to be directed in a preselected reverse direction, which is defined by said at least one guiding seat (16a, 16b, 17a, 17b), - and vice versa characterized in that said at least one guiding seat (16a, 16b, 17a, 17b) comprises at least one second guiding seat 17a, 17b), which is open so as to pass through a second end of said lever, which is opposite with respect to a first end.