Titania (TiO2) or silica (SiO2) supported ruthenium-iron catalysts were prepared by the dry co-impregnation, using aqueous solutions of their chlorides precursors. This study analyzes the structural characteristics influence of these supports, as well as that of the iron additive, over the performance of these catalysts on the partial hydrogenation of benzene. The results of the X-ray diffraction (XRD) analyses, oxygen chemisorption and temperature programmed reduction (TPR) have showed that the reducibility and dispersion of metallic phase strongly depend on the support structural characteristics. These analyses have also revealed the influence of the iron over supported ruthenium morphology and its catalytic performance. That influence was more significant on the ruthenium catalysts supported by silica. Higher selectivity in cyclohexene was observed on the titania supported ruthenium catalysts, opposite to those supported on silica. (C) 2003 Elsevier B.V. All rights reserved.