A quick-change system for a tool holder comprises a machine-side receiving fixture having a hollow-cylindrical extension on which a switching sleeve is displaceably held. Automatic angular alignment of the tool holder upon introduction into the hollow-cylindrical extension of the receiving fixture is enabled by an alignment of the points of the star-shaped end face on the cylindrical holding portion of the tool holder, upon impact against a first set of three balls angularly spaced 120° apart. Once the tool holder has aligned itself in this way, then the first balls make their way into the longitudinal grooves of the cylindrical holding portion, whereby a rotationally fixed coupling is achieved. Upon the further insertion into the hollow-cylindrical extension, an axial securement finally occurs when a second set of three balls are displaced radially inward into associated depressions on the cylindrical holding portion.