ABSTRACTIn this study, the removal of sulfur compounds from diesel samples using ultrasound-assisted oxidative desulfurization (UAODS) process in presence of different types of oxidizing agents was studied. Experiments were performed to assess the effects of influential parameters on the performance of UAODS process including ultrasonic irradiation time, oxidant type, mass ratio of oxidant to diesel fuel (oxidant: diesel), and finally acetic acid as an oxidative promoter. The efficiency of sulfur compounds removal from the diesel fuel dramatically improved using appropriate oxidative process with the assistance of ultrasound irradiation. H2O2 was found to be the most promising oxidant component whose concentration in the media directly affected total sulfur removal and thiol group conversion efficiencies. Using 4 wt% of H2O2 followed by 15 min of ultrasonic irradiation leaded to sulfur removal efficiency of 76% and thiol group conversion of 79% at ambient temperature and atmospheric pressure. Using acid acetic as the promoter of H2O2 also leaded to further sulfur compounds removal.