PROBLEM TO BE SOLVED: To provide a material and method for acoustical board strengthening and repair that may be implemented promptly and extend the service life of the acoustical board.SOLUTION: An acoustical board strengthening and repair material 10 includes a front surface plate part 11 installed at a lower part of the front surface of a front surface plate 21 of an acoustical board 20, and a folded part 12 that is bent upward from the lower edge part of the front surface plate part 11, so as to cover the lower edge part of the front surface plate 21. By fitting the lower edge part of the front surface plate 21 in the folded part 12 and positioning the front surface plate part 11 at a lower part of the front surface of the front surface plate 21, a horizontal crack may be inhibited that extends along the lower edge of the folded section at the lowest tier of a perforated part 21B of the front surface plate 21.
