Abstract: A process for the preparation of a catalyst is described, said catalyst comprising at least one inorganic refractory support, at least one halogen or halogenated compound at a content greater than 0.1% by weight, at least one metal from group VIII of the periodic classification (platinum, palladium, nickel and ruthenium) and at least one additional metal M selected from germanium, tin, lead, iron, titanium and chromium. The process is characterised in that said metal M is introduced in the form of at least one orqanometallic complex. The catalyst prepared in accordance with the invention may be used for dehydrogenation reactions, particularly of paraffinic hydrocarbons and olefinic hydrocarbons.