This device comprises a slideway inside which the base 2 of the corresponding binding is slidably mounted. One side of this slideway includes notches or the like 7 intended to receive one or more immobilization teeth. These teeth 8 are carried by a bolt 9 mounted so as to be movable transversely inside the base 2 of the binding. Over at least a part of the length of this bolt 9, play is provided between one of the edges thereof and the adjacent wall of its housing 10. A buffer 13 made from elastic material is interposed at this point. A rotary blocking cam 16 is arranged so as to act directly on the end of the immobilization bolt 9 which is opposite that carrying the teeth 8 of the latter.; The arrangement of this cam is such that, in its locking position, it exerts a thrust R diagonally on the bolt, having the result both of engaging its teeth 8 in the corresponding notches 7 of the slideway and of compressing the elastic buffer 13 arranged against this bolt. This device is intended for equipping ski bindings in order to permit the adjustment of the position thereof in the longitudinal direction.