To enlarge a usable space in a lower part of a winding part of a slitter device to facilitate rewinding operation and reduce cost greatly when compared with a slide system.

In this slitter device cutting a large width web S into a plurality of small width webs S' in the longitudinal direction, separating the cut small width webs S' in the front and the rear, and winding them by individual winding devices W1, W2 arranged each in the front and the rear, turn center P of a winding beam 4 to which a winding frame 5 provided so as to cross in the direction of right angle is attached is provided in an upper part of the winding part for the direction of flow of the webs to turn the winding beam and the winding frame 5 using the turn center P as a supporting point.