Some applications of fractals to acoustics were presented, which include wave scattering on fractal surface and sound attenuation caused by the aggregations consisting of non-spherical grains. A successful explanation to the experimental results of underwater acoustical reverberation summarized by Schulkin and Shaffer was given by the former theory. The fractal dimensions of the non-spherical grains and their agglomeration can be obtained by the latter theory. Comparisons of the theories with experiments were given.