The invention relates to a hydrotreatment catalyst and an application thereof. The catalyst comprises a carrier and hydrogenation active metal components loaded on the carrier. The catalyst is characterized in that the hydrogenation active metal components are nickel, cobalt and molybdenum. In terms of oxides based on the weight of the catalyst, the sum of the contents of nickel and cobalt is 2-10wt% and the content of molybdenum is 10-30wt%, wherein the atomic ratio of nickel to cobalt is 1.4-10. The catalyst is suitable to be used in hydrocarbon oil hydrotreatment for preparing clean oil products.