The invention relates to a rotor (1), in particular gas turbine rotor, having a plurality of rotor discs (3), which each have an axial through-opening (2), which rotor discs are axially stayed by means of at least one tie rod (5), which extends through the through-openings (2), and which rotor discs are assembled to form at least one rotor disc unit (7, 8), at least one support ring (11) bearing against the outer diameter of the tie rod (5), which support ring is engaged with one of the rotor discs (3) and via which the tie rod (5) is supported on the rotor disc (3), and at least one securing element (14) being provided for axially securing the at least one support ring (11), characterised in that the securing element (14) has an annular design and is fastened to the rotor disc (3) to which the support ring (11) is connected and is formed such that the securing element fits around an end face (15) of the support ring (11) that faces away from the rotor disc (3).