A radial shaft sealing ring, especially for use together with a CO2 containing pressure medium, comprises a membrane body (1) and a supporting body (2). A centering element (5) having a radially outer edge (6) is disposed on the supporting body (2) and is not covered by the membrane body (1). The membrane body (1), on its radially inner end, comprises a tilted sealing lip (11) which faces away from the supporting body (2). The supporting body (2) has an axial bore for the shaft (8) and, opposite the sealing lip (11), a supporting face (13) which slopes towards the wall (12) of the bore. The invention is characterized in that the centering element (5), when the radial shaft sealing ring is fitted in a bearing house (4), can be contacted with the interior of the bearing housing (4) in a press fit and that the angle (α) between the supporting face (13) and the wall (12) of the bore of the supporting body (2) ranges between 45° and 55° in a central plane which includes the axis of the radial shaft sealing ring.