An adjusting device having a carriage supporting a binding part, and a base plate supported on the ski and serves to guide the carriage for movement relative to the ski, whereby one of the carriage and the base plate is equipped with serrations which extend in a longitudinal direction of a ski, with which is associated a locking member which is guided on the other of the carriage and the base plate for movement transversely with respect to the longitudinal direction of the ski and has locking teeth thereon. In order to create in this adjusting device a positive locking of the teeth of the locking member with respect to the serrations, the invention provides that one end of an intermediate member be hinged to a locking member or to a swivel part which is hingedly connected to the locking member. The intermediate member is pivotal between first and second positions located on opposite side of a dead-center position thereof. The other end of the intermediate member is hingedly supported on the carriage which carries the locking member and which, in the locked condition of the adjusting device, is provided in a second position on an opposite side of a dead-center position from said first position.