The invention relates to a safety ski binding and in particular, a heel support having a base plate supporting a vertical pivot, the heel support being fastened to the upper side of the ski. The heel support includes a sole support being upwardly pivotable against detachable locking and a support plate for the heel of the ski boot, which can be pivoted about a vertical axle. The support plate is pushed by a spring into its central position along the ski. To shift in such a ski binding the axis of rotation for the ski boot is essentially an extension of the shinbone of the skier. Thus, the pivot is located between the front jaw and the heel support and the support plate is pivotally mounted at the pivot. The heel support is opened in a horizontal release process by a control mechanism formed by a roller and a cam. The roller is mounted in the base plate by means of its axle extending in the longitudinal direction of the ski. The roller cooperates with a control element to actuate the detachable locking of the heel support.