On a solid surface the effects of the implosion of the bubbles, created during a sonication run, are commonly used to clean or to erode the surface itself. In the present work, ultrasound was used in order to obtain a ruthenium on alumina catalyst distinguished by a very high value of the dispersion of the metal. The samples were characterized with different techniques in order to study the influence of the sonication on both the metal crystallites and the support.