The invention relates to a preparation method of a vulcanization type hydrofining catalyst. A needed catalyst carrier is impregnated by adopting an impregnation solution, and then the vulcanization type hydrofining catalyst is obtained by in-situ crystallization reaction and thermal treatment. The preparation method is characterized in that the impregnation solution contains active metal ammonium molybdate and/or ammonium tungstate, and an inorganic salt precursor of Ni, and/or Co, and contains a vulcanizing agent, an organic complexing agent and a cosolvent simultaneously. The preparation method provided by the invention solves the problems that a conventional oxidation state catalyst is long in vulcanization time when starting work, and high in operation cost, and overcomes the shortcomings of more preparation steps and high cost of the vulcanization type hydrofining catalyst. The catalyst prepared by the method provided by the invention is applicable to petroleum fraction hydrofining treatment, and simpler and more convenient than other ex-situ vulcanization methods, and the hydrogenation activity of the catalyst prepared by the method can reach or exceed the effect of catalysts prepared by in-situ vulcanization.