The sonochemical process is evaluated as an effective and feasible method for the control of sulfur in coal. In the presence of a small amount of hydrogen peroxide, the sonochemecal process can significantly bring sulfur from the coal matrix into solution as sulfate ion. Results also indicate that hydrogen peroxide can significantly enhance the rate and the extent of sulfur oxidation. Room temperature appears to be the most optimal situation for sulfur oxidation. As temperature increases to 500C, the effectiveness of the sonochemical process suffers due to the fast decomposition of hydrogen peroxide. Increasing energy density increases the rate and the extent of sulfur oxidation. Under the experimental conditions of this study, further increase in energy density yields no further increase in both the rate and the total oxidizable sulfate.