To wind up a paper strip around a bundle of paper sheets without winding up the paper sheets and bind them with the paper strip.

A strip body L fed out by a paper strip supplying part 41 is gradually wound onto a bundle of paper sheets that are held and rotated by paper bill press guides 24, 25, 26, and 27 provided at a rotary drum 22 while a feeding-out speed and a feeding-out amount of the strip body L fed out by the paper strip supplying part 41, a moving speed and an amount of motion of a bill pressing part 2 in its horizontal direction and a rotating speed and an amount of rotation of the rotary drum 22 are aligned to each other.