Ni-W catalysts were prepared by impregnation of commercial gamma -alumina and silica supports. The sulfidation, performed directly after drying at 100 degreesC, yielded fully sulfided Ni-W species on both supports (SEM-EDAX, XPS, XRD). At optimal metals loading (similar to 50 wt% NiO + WO3, Ni/W = 2), the sulfided catalysts had similar texture (N-2 adsorption) and displayed similar activity in dibenzothiophene hydrodesulfurization (DBT HDS), while the activity of the Ni-W/SiO2 catalyst in toluene hydrogenation (HYD) was six times higher than that of Ni-W/Al2O3. This is due to the more than two times higher WS2 slabs stacking number in Ni-W/SiO2 compared with Ni-W/Al2O3 (XRD, HR-TEM), yielding stronger adsorption of toluene (TPD).