To provide winding base material and package and a slitter, having excellent packaging fitness for packing a material to be stored using a sheet or a winding base material, both ends of which are half-cut parallel, easily folding the sheet or the winding base material in storing the material to be stored, and finely forming a folded packaged body.

In this package using the winding base material and the packaged body using it where a winding web at least one side of which is provided with a sealing layer is slit or simultaneously half-cut, half-cuts are make parallel at both ends of the winding base material.