WINDING DEVICE AND WINDING METHOD

According to one embodiment, a winding device includes, a winding core having a non precise circle cross-section perpendicular to a direction in which a center of rotation extends, and a holding device including a first holding section and a second holding section configured to hold the windable material therebetween such that an imaginary line which passes between the first and second holding sections and extends perpendicular to a direction in which the windable material is introduced between the first and second holding sections and the extending direction of the center of rotation passes through a position off the center of rotation and that at least part of the winding core overlaps the imaginary line while the winding core is rotating.