A single-motor-driven gravure cylinder chuck mechanism to be used for a processing unit of a fully automatic gravure plate-making processing system for manufacturing a plate-making roll by performing a series of processes on an unprocessed plate-making roll, the single-motor-driven gravure cylinder chuck mechanism comprising: a pair of chuck cones (16a, 16b) provided to be opposed to each other, for chucking both end surfaces (14a, 14b) of the unprocessed plate-making roll; a chuck cone moving means for allowing the pair of chuck cones to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll, said chuck cone moving means comprising a pair of ball screws (26a, 26b), one of said ball screws being located opposite to another one of said ball screws, each of said ball screws comprising a threadedly engaging ball screw nut (24a, 24b) with a screw shaft (22a, 22b), said chuck cone moving means further comprising an elongated rod member, said pair of ball screws engaging the elongated rod member such that the pair of chuck cones are allowed to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll, respectively, the chuck cone moving means further comprising chuck cone gripping members (28a, 28b) mounted to the ball screw nuts, for gripping rear end portions of the pair of chuck cones, respectively; and a single motor for driving the chuck cone moving means, the single motor allowing the pair of chuck cones to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll so that the pair of chuck cones chuck the unprocessed plate-making roll, said elongated rod member being connected to said single motor, wherein said elongated rod is rotatable via said single motor. a pair of chuck cones (16a, 16b) provided to be opposed to each other, for chucking both end surfaces (14a, 14b) of the unprocessed plate-making roll; a chuck cone moving means for allowing the pair of chuck cones to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll, said chuck cone moving means comprising a pair of ball screws (26a, 26b), one of said ball screws being located opposite to another one of said ball screws, each of said ball screws comprising a threadedly engaging ball screw nut (24a, 24b) with a screw shaft (22a, 22b), said chuck cone moving means further comprising an elongated rod member, said pair of ball screws engaging the elongated rod member such that the pair of chuck cones are allowed to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll, respectively, the chuck cone moving means further comprising chuck cone gripping members (28a, 28b) mounted to the ball screw nuts, for gripping rear end portions of the pair of chuck cones, respectively; and a single motor for driving the chuck cone moving means, the single motor allowing the pair of chuck cones to be freely brought into contact with and separated away from both the end surfaces of the unprocessed plate-making roll so that the pair of chuck cones chuck the unprocessed plate-making roll, said elongated rod member being connected to said single motor, wherein said elongated rod is rotatable via said single motor.