An axial bearing for a high speed open-end spinning rotor mounted without axial thrust in a support disc bearing arrangement has a static magnetic bearing component secured in a bearing housing with at least two axially polarized permanent magnet rings limited by pole discs, and a dynamic magnetic bearing component having ferromagnetic webs on the rotor shaft at the spacing of the pole discs. The static magnetic bearing component (27) is arranged inside a plastic bearing bush (30) and secured by a plastic closing lid (31). The front side of the closing lid (31) has a stop journal (50) forming an axial emergency operation bearing and the rear side has a conically widened fastening lug (51) which is elastically deformed as installed.