Co(II) porphyrins have been utilized as efficient and selective catalysts for the extractive oxidative desulfurization reaction on the refractory dibenzothiophene (DBT) in [Formula: see text]-dodecane (model middle distillate fuel oil). The acetonitrile was taken as extracting polar solvent and H2O2 was used as oxidant. The reaction optimization was done with respect to DBT:catalyst molar ratio; DBT:H2O2 molar ratio; extracting solvent: CH3CN/[Formula: see text]-dodecane volume ratio; reaction temperature and time. Under the optimized conditions, a maximum of [Formula: see text]98% DBT removal was achieved by using the meso-tetrakis(4[Formula: see text] methoxyphenyl)porphyrinatocobalt(II) as catalyst under mild conditions at 50[Formula: see text]C.