Abstract: The self-locking binding is adapted for automatically locking the lower toe portion of cross-country skiing footwear to a cross-country ski. The binding comprises a plate, associable with a ski which is adapted for engagement with a front oscillable element, forming a toe seat, the movement whereof is allowed by the interposition of a spring element between it, the plate, and a front release block. Rearward of the oscillable element there is journalled an adjustable device for locking the toe portion of a cross-country skiers' footwear in position, the toe portion being releasable from the oscillable element which is adapted to enable adjustment of its excursion.