Rewinder for the production of paper logs adapted to guide and transversely pre-cut a paper web along a predetermined path, adapted to wind a predetermined amount of the paper web on a core in a winding station, and including a threading mechanism for threading the web along said path. The threading mechanism includes a dragging unit provided to engage the web to drag it along the path with a predetermined feed direction and at least one dragging member to engage a respective flap of the web preceding the production of the logs. The dragging unit is located downstream of the winding station and is adapted to release the flap of the web from the dragging member, the release means being arranged downstream of the dragging so as to intercept the flap of the web and disengage it from the dragging while the web is fed.