To provide a building material mounting method which enables construction without the removal of an existing material such as a frame and an electric workpiece, and a fixing implement for use in the building material mounting method.

This building material mounting method for mounting an approximate rectangular parallelepiped-shaped sound-absorbing material 42 on an indoor wall surface 11 is characterized as follows: one or more lines 41 are laid in a tensioned state between the two or more frames 26 which are vertically installed at a predetermined distance from the wall surface 11 almost in parallel with the wall surface 11; and the sound-absorbing material 42 is arranged between the line 41 or the frame 26 and the wall surface 11, so that the sound absorbing material 42 can be mounted on the wall surface 11.