Rotary press

A rotary press includes a printing unit, folding machine, dancer roller, motor, tension detection unit, and control unit. The printing unit prints on a web supplied from a winding roll. The folding machine folds the printed web supplied from the printing unit. The dancer roller retreats from and advances to a web traveling path between the printing unit and the folding machine, during printing and plate mounting, respectively, to come into contact with the web. The motor selectively, rotatably drives the winding roll in a reel-out direction and a winding direction. The tension detection unit detects a tension of the web between the winding roll and the printing unit. The control unit controls the motor on the basis of a detection result of the tension detection unit during plate mounting.