To provide a belt-like sheet binder wrapped around a hollow cylindrical shape not requiring a winding drum for transporting a long belt-like sheet formed in a spiral tube by spirally winding it and a method of unbinding the band-like sheet binder.

In this long belt-like sheet binder wrapped around in the hollow cylindrical shape, the belt-like sheet is wrapped around on a winding shaft formed by arranging parallel with each other and combining a plurality of rigid center side bar bodies so that their axes are disposed on a circumference at approximately equal intervals in the hollow cylindrical shape with a winding width narrower than the length of a center side bar body. The rigid outer bar body longer than the winding width of the wrapped around belt-like sheet is disposed at a position where outermost surface part of the belt-like sheet at its winding end crosses the extension of a line connecting the center of the winding shaft to the center side bar body so as to be parallel with the center side bar body in pairs. The both end parts of the center side bar body and the outer bar body in pairs are detachably fastened to each other with fasteners.