The invention relates to a sealing ring (1) for sealing a piston rod comprising a retaining ring (2) having a circular inside diameter (M1) and a center axis (M) and comprising a plurality of sealing segments (3), which are supported in the retaining ring (2) in such a way that the sealing segments can be moved in a direction radial to the center axis (M), wherein each sealing segment (3) has a sealing surface (3a) that is oriented toward the center axis (M) and that extends in a curved manner in a circumferential direction (U) with respect to the center axis (M), and wherein each sealing segment (3) has two lateral sealing-segment guiding surfaces (3b) extending parallel to each other, wherein the sealing surface (3a) ends at one of the two sealing-segment guiding surfaces (3b) at both ends, and wherein the retaining ring (2) comprises a plurality of guiding segments (2a) arranged at a distance from each other in the circumferential direction (U), wherein each two guiding segments (2a) following each other in the circumferential direction (U) have guiding surfaces (2b, 2c) that face each other and that extend parallel to each other, said guiding surfaces being arranged at a distance from each other in such a way and being designed in such a way that, by means of the sealing-segment guiding surfaces (3b) of the sealing segment, the sealing segment (3) is guided on the two lateral guiding surfaces (2b, 2c) and is supported on the two lateral guiding surfaces in such a way that the sealing segment can be moved in the radial direction (R), wherein guiding segments (2a) and sealing segments (3) are arranged in succession in the circumferential direction (U).