An arm for guiding paper fed along a paper feed path is swingably supported at its base end portion on one side of the winding core. The arm is provided with a free roll, on which the paper is guided to pass onto the winding core. At its free end portion, the arm has a roller rotatably mounted thereon which constitutes a body of rotation contacting with the paper roll so that with the winding core rotated and with the roller pressed against the paper roll the paper may be wound up into the paper roll on the rotating winding core without the occurrence of a paper winding wrinkle, whereby with a distance held constant at all times between the feed roll and the roller along a paper winding path, paper winding without such wrinkling can be achieved to yield a paper roll that is large in its maximum diameter.