Abstract: The oxidation of dibenzothiophene (DBT) in decalin (as solvent) was conducted using oil-soluble oxidant cyclohexanone peroxide (CYHPO).The effects of oxidant amount, reaction temperature, reaction time were investigated in detail. The results showed that under the condition of ratio of CYHPO to sulfur 2.5∶1, reaction temperature 100℃ and reaction time 3h, the desulfurization rate was up to 87%. The little water produced after oxidation was removed by molecular sieve adsorption. The recovery ratio of model oil was up to 98% after the treatment with centrifugation and adsorption.