PURPOSE: To eliminate the need to apply paste at site by a method wherein wallpaper one side of which is covered with paste is folded in such a manner that said side is directed inwards, and said wallpaper is tightly sealed in a packaging bag filled with inert gases.

CONSTITUTION: Wallpaper 3 is prepared by forming a surface 5 covered with paste on one side of base sheet 4, and said wallpaper 3 is folded so that the surface 5 faces inwards and tightly sealed in a packaging bag (a). The space 6 in the sealed bag (a) is filled with inert gases such as nitrogen. Since the surface 5 is folded so as to face inwards, the surface 5 is prevented from contacting the inner surface of the bag (a). And the bag is filled with inert gas and tightly sealed, so that the paste is not dried, and hence the wallpaper 3 can be applicable as it is at the site.