Abstract: A catalyst for hydrotreating, especially hydrodesulfurization, of residua and heavy crudes is prepared by synthesizing the support from titanium and boehmite, to form either a titanium/alumina support (TiO2/Al2O3) or a titanium-alumina support (TiO2—Al2O3) that is thereafter provided with at least one hydrogenating metal from group VIB in oxide form and a promoter from group VIII also in oxide form. The (TiO2/Al2O3) support is prepared from boehmite, which is peptized by using an inorganic acid, then extruded, calcined and impregnated with a solution containing titanium, while the (TiO2—Al2O3) support is prepared by admixing boehmite with a titanium-containing solution, peptized using an inorganic acid, extruded and calcined to obtain the titanium-alumina support.