New sulfide metal catalysts are described, containing Ni, Mo and W, an element Z selected from Si, Al and mixtures thereof, and possibly an organic residue, obtained by sulfidation of mixed oxide precursors, also new, characterized in that they comprise an amorphous phase and a wolframite iso structural crystalline phase, the crystallinity degree of said mixed oxides being higher than 0 and lower than 100%, preferably higher than 0 and lower than 70%. The catalysts of the invention are useful as hydrotreatment catalysts, and in particular as hydrodesulfurization, hydrodenitrogenation and/or hydrodearomatization catalysts.