A rotor blade system includes a blade root, a blade neck adjoining the blade root, an airfoil adjoining the blade neck, a radially outer partition wall, an axially forward partition wall and an axially rearward partition wall, connected to the radially outer partition wall such that the partition walls surround the blade neck on three sides, the partition walls projecting beyond the blade neck in the circumferential direction, and further including a blade root protection plate designed to be arranged on the blade root. It is provided that the blade root protection plate have at least one sealing portion that extends in the axial direction from the forward partition wall to the rearward partition wall and whose radially outer side is disposed opposite the radially outer partition wall when the blade root protection plate is arranged on the blade root.