Dibenzothiophene (DBT, a typical sulfur compound) and dibenzothiophene sulfone (DBTO2, an oxidation product of DBT) were chosen as the model compounds, and their adsorption over a mesoporous silica (MCM-41) and a mesoporous carbon (CMK-3) were conducted under the exact same conditions. The adsorption amounts of DBTO2 over both adsorbents were enhanced compared to the DBT adsorption amounts, which clearly demonstrated that a combination of oxidation and adsorption is better than direct adsorption to achieve a better desulfurization performance. Besides, it was found that CMK-3 performed better for DBT removal compared to MCM-41, but the adsorption amount of DBTO2 over MCM-41 exceeded the corresponding value over CMK-3 (1.60 vs 0.88 mgS/g in p-xylene). Moreover, model fuels with varied hydrocarbon compositions were employed to investigate the impact of arene amounts. Finally, jet and diesel fuels were oxidized and treated with MCM-41, resulting in 85.6% and 81.4% sulfur removal, respectively. In contrast, when the fuels were directly treated with MCM-41, the corresponding sulfur removal amounts were only 19.8% and 40.9%. The results with real fuels further verified the necessity of the oxidation process. A simple washing method was found to be effective for regeneration of the adsorbent.