Recent studies performed mainly in the author's laboratory are reviewed regarding the quantitative measurements of acoustic velocities with acoustic microscopes. An interference microscope is described which measures acoustic velocities in thin biological materials. On the other hand, velocities of leaky surface acoustic waves can be measured by an acoustic microscope in a nonscanning operation. The principle of the velocity measurements is described, and a new construction for the acoustic microscope is described in which a linearly focused acoustic beam is introduced to investigate anisotropies of crystals such as Z-cut sapphire and Y-cut LiNbO3.