The aromatic oil, which is a byproduct of the processes of naphtha steam cracking (NSC), was hydrocracked with Mo-, Co-, and Mo-Co-loaded zeolite catalysts. Experiments were performed at a temperature range of 375-450 degrees C. The initial hydrogen pressure was 10 MPa, and the reaction time was 90 min. The main fraction of the reaction product, the liquid portion, was investigated from a hydrogenation and cracking point of view. The loading of the metal oxide on zeolite increased the cracking and hydrogenation performance of the catalysts. Molybdenum had a good hydrogenation effect, whereas cobalt had a good cracking effect. Comparing the hydrogenation and cracking performance of one-metal-loaded catalysts to those of two-metal-loaded catalysts, the cracking effect of two-metal catalysts was much more than one-metal catalysts. However, the hydrogenation performance of one-metal and two-metal catalysts were approximately equal to each other. The activated catalysts were also used in experiments. The activation of unloaded zeolite catalysts was more effective on the cracking performance of the catalyst. The Liquid fractions of the reaction products were also separated into aliphatic, aromatic, and polar fractions by liquid absorption chromatography. The results showed that the type of the catalyst was not effective on the distribution of aliphatic, aromatic, and polar fractions. It was observed that a portion of the aliphatic compounds converted to aromatics at temperatures higher than 425 degrees C. At the end of this study, a valuable liquid product to be burnt, such as fuel oil, was obtained from aromatic oil.