In a proof printing press, a length of an outer circumference of a plate cylinder at a downstream side of a facing position P1 in a rotation direction is longer than a length in a circumferential direction of a mounting surface of the plate cylinder, where the length of the outer circumference of the plate cylinder extends between the facing position P1 where the plate cylinder faces a collecting cylinder and a facing position P2 where the plate cylinder faces a wiping roller, and a length of the outer circumference of the plate cylinder at a downstream side of the facing position P2 is longer than the length in the circumferential direction of the mounting surface of the plate cylinder, where the length of the outer circumference of the plate cylinder extends between the facing position P2 and a facing position P3 where the plate cylinder faces an impression cylinder.