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 3h,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.