Abstract: The photocatalytic oxidation of dibenzothiophene (DBT) in noctane (as solvent) was conducted using H2O2 as oxidant， TiO2 loaded on activated carbon as photocatalyst and 30W ultraviolet lamp as light source. The effect of calcination temperature and the amount of TiO2 loaded on activated carbon, photocatalyst amount, H2O2 amount and the radiation time on the removal ratio of DBT were investigated in detail. The results show that the TiO2/activated carbon prepared by solgel method has good catalytic activity to DBT oxidation. The optimal photocatalytic oxidation conditions of DBT are 400℃of calcination temperature， 32% of the amount of TiO2 loaded on activated carbon, 0.7g/100mL of the amount of photocatalyst and 10mL ( O/S(mol ratio)= 14) of the H2O2 amount. Under optimal conditions, the removal ratio of DBT is up to 90% by 8h radiation time. The photocatalytic oxidation of dibenzothiophene (DBT) DBT reaction is a firstorder reaction.