A rotor disk arrangement having a rotor disk which has, distributed around the outer circumference, a plurality of axially extending blade holding grooves and an encircling fastening protrusion and/or a plurality of fastening protrusions arranged in a circumferentially distributed manner, and having a plurality of sealing elements arranged in a circumferentially distributed manner, the sealing elements covering the blade holding grooves at least in portions on the end side and having, on the side facing the rotor axis, at least one fastening portion that bears against the underside of the fastening protrusion, wherein the fastening protrusion is embodied in an undercut manner, wherein the distance thereof from the rotor axis at the free end facing away from the rotor disk is less than in a region within the fastening protrusion.