The said catalyst is used in hydrogenating petroleum material, especially heavy oil, to produce high-grade lubricant base oil. The catalyst and pore enlarging agent has Al2O3 -SiO2 as carrier to carry Ni, Mo or W and contains at least one assistant. It features its high metal content, over 50%, and crushing strength greater than 100 N; and under the action of pore enlarging agent, over 30% pores have pore diameter in the range of 60-100A and the surface area of the catalyst reaches 110-230 sq m/g. The catalyst has high hydrogenation acativity and stability and can result in lubricant base oilwith viscosity index greater than 98 and paraffin base oil yield greater than 70%.