Provided is a single-motor-driven gravure cylinder chuck mechanism that is enhanced in contact tightness of chuck cones with respect to an unprocessed plate-making roll in each processing unit of a fully automatic plate-making system. The gravure cylinder chuck mechanism is to be used for a processing unit of the 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 gravure cylinder chuck mechanism includes: a pair of chuck cones provided to be opposed to each other, for chucking both end surfaces of the unprocessed plate-making roll; 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; and a single motor for driving the chuck cone moving means. The single motor allows 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.