Cracked Fuel Oil (CFO) is a low price byproduct of olefin production units in petrochemical plants. The components of this product are mainly aromatic compounds with two or more benzene rings or even polyaromatic compounds. Today the main application of CFO in the country is production of carbon powder used in the tire industry. Also the CFO produced in olefin units working with naphtha feedstock contains significant amounts of naphthalene (10 to 30 percent). Therefore, CFO is also used in some plants for the extraction of naphthalene. On the other hand, CFO also contains some other valuable compounds such as the methyl naphthalene compounds which their extraction may lead to produce added value products. In this research work possibility of the isolation of naphthalene and methyl naphthalene from CFO feedstock of Amir Kabir Petrochemical Complex with a combined method of steam distillation and solvent extraction was investigated. Based on previous experiences, the main objective of this study was the study on the effects of operating parameters of duration and temperature of steam distillation on the quality of the resulting product of steam distillation process. Also, another goal of this study was to evaluate the quality of the condensed water and possible water reuse. Based on the observations made in the experiments, best results were obtained at a temperature of 125 °C. In this condition, maximum percentage of extraction for each of the desired compounds (approximately 60% for naphthalene, and 48% for methyl- naphthalene) was obtained through distillation. In this condition the lowest amount of water was consumed, and based on the COD tests, water pollution was at its lowest amount. Also the amount of tio-naphten, which is an undesirable sulfur containing compound, was reduced from 0.09% in the feed stock to 0.01% in the distillation product. Keywords: fuel oil, naphthalene, methyl naphthalene, steam distillation, the amount of COD