Pd-mordenite (PdMOR), Pd-beta (PdBETA), and Pd-ZSM-5 (PdZSM-5) agglomerated with bentonite (Bent) were tested in the hydroisomerization of a C7-C8 fraction obtained by distillation of a real naphtha stream. Depending on the catalysts, the overall paraffins conversion obtained decreased in the following order: PdBETABent > PdMORBent > PdZSM-5Bent. Concerning the hydroisomerization products, the absence of methane and ethane revealed that hydrogenolysis did not contribute to cracking reactions. High aromatic and particularly benzene conversion was reached. Methylcyclopentane and cyclohexane were the typical products obtained during the hydrogenation of benzene over bifunctional catalysts, whereas methylcyclohexane was the main product in the hydrogenation of toluene. Some isomerization and ring-opening reactions were produced from these naphthenic compounds. Finally, the research octane number (RON) of the product stream was estimated. The increase of the RON was significantly higher in the catalysts based on agglomerated beta zeolite, because of the high amounts of multibranched isomers and aromatic compounds in the product stream, always satisfying the limits imposed by legislation.