A sheet-fed offset rotary
printing press includes one plate cylinder, one
blanket cylinder with the same size as that of the plate cylinder, one impression cylinder, one plate making device, four inking devices, four roller throw-on / throw-off devices, and a cylinder throw-on / throw-off device. At least one plate is mounted on an outer surface of the plate cylinder. The
blanket cylinder opposes the plate cylinder, and at least one
blanket is mounted its outer surface. The impression cylinder has at least one gripper device for holding a
paper sheet. The plate making device can inscribe four printing patterns on four regions of the plate. The inking devices individually supply inks to the four printing patterns of the plate on the plate cylinder through four ink form rollers. The roller throw-on / throw-off devices throw on one ink form roller onto corresponding one printing pattern of the plate and throw off the remaining ink form rollers from the remaining printing patterns. The cylinder throw-on / throw-off device throws on the blanket cylinder supplied with the inks immediately before it opposes the
paper sheet held by the gripper device, and throws it off before it opposes the impression cylinder while the gripper device does not hold a
paper sheet.