The separation of olefin from heavy fluid catalytic cracking (FCC) naphtha is beneficial to avoid the loss of octane number during the desulfurization process. Extractive distillation is a promising alternative to separate olefin and enrich sulfide at the same time. The vapor-liquid equilibrium of heavy FCC naphtha with different single solvents was studied first. Sulfolane showed the best ability to separate olefin with a selectivity coefficient theta of 2.81; however, sulfide selectivity coefficient beta was only 1.78. N-Methylpyrrolidone showed the best ability to concentrate sulfide, with beta up to 2.07 but lower B of theta 2.74. The optimized dual solvent with a volume ratio of sulfolane/N-methylpyrrolidone at 85:15 (vol %) resulted in a selectivity coefficient B of up to 4.01, while beta was 1.97.