To provide a cushioning material made of paper, capable of being easily assembled from one sheet blank and being simply disassembled even when the cushioning material is discarded.

Side wall sheets 21 and 22, top sheets 31 and 32, and inner wall sheets 41 and 42, both the edges thereof being projected from a bottom sheet 10, are successively and connectively provided to mutually opposed two sides of the rectangular bottom sheet 10. Insertion pieces 43 and 44 are respectively provided to the edges of the inner wall sheets so as to protrude outward. Second inner wall sheets 11 and 12 and folding pieces 13 and 14 are respectively provided connectively to the other two sides of the bottom sheet, which are mutually opposed to each other, and side pieces 15, 16, 17 and 18 are respectively provided connectively to the other edges of the second inner wall sheets, to which the bottom sheet and the folding pieces are not connectively provided. A bottom sheet cut j is provided in the central part of the bottom sheet, and inner wall sheet cuts k and l, which are positioned on the same line as the bottom sheet cut, are provided in the inner wall sheets, respectively. Further, cuts m are respectively provided in the edges of each inner wall sheet, which are closer to the top sheet. A sheet blank thus formed are folded and assembled to the cushioning material.