A method for preparing hexadecahydropyrene, comprising: controlling a hydrocarbon oil raw material that contains pyrene compounds to have a hydrogenation reaction in the presence of a hydrogenation catalyst, wherein the pyrene compounds are selected from at least one of pyrene and unsaturated hydrogenation products thereof, the hydrogenation catalyst contains a carrier and an active metal component loaded on the carrier, the active metal component is Pt and/or Pd, and the carrier contains a small crystal size Y zeolite, alumina and amorphous silica-alumina, the small crystal size Y zeolite has an average grain diameter of 200-700nm, a molar ratio of SiO 2 /Al 2 O 3 of 40-120, a relative crystallinity of ≥95%, a specific surface area of 900-1,200m 2 /g, and the pore volume of secondary pores in 1.7-10nm diameter accounts for 50% or more of the total pore volume; preferably, wherein the average grain diameter of the small crystal size Y zeolite is 300-500nm, the relative crystallinity is 95-120%, and the pore volume of secondary pores in 1.7-10nm diameter accounts for 50-80% of the total pore volume; preferably, wherein the small crystal size Y zeolite has a lattice constant of 2.425-2.435nm and a pore volume of 0.5-0.8mL/g; and wherein the hydrogenation reaction process includes two stages of reaction that are executed sequentially, the percentage content x 1 of the active metal component in the hydrogenation catalyst used in the first stage of reaction is lower than the percentage content x 2 of the active metal component in the hydrogenation catalyst used in the second stage of reaction, and the percentage content y 1 of the small crystal size Y zeolite in the hydrogenation catalyst used in the first stage of reaction is higher than the percentage content y 2 of the small crystal size Y zeolite in the hydrogenation catalyst used in the second stage of reaction. controlling a hydrocarbon oil raw material that contains pyrene compounds to have a hydrogenation reaction in the presence of a hydrogenation catalyst, wherein the pyrene compounds are selected from at least one of pyrene and unsaturated hydrogenation products thereof, the hydrogenation catalyst contains a carrier and an active metal component loaded on the carrier, the active metal component is Pt and/or Pd, and the carrier contains a small crystal size Y zeolite, alumina and amorphous silica-alumina, the small crystal size Y zeolite has an average grain diameter of 200-700nm, a molar ratio of SiO 2 /Al 2 O 3 of 40-120, a relative crystallinity of ≥95%, a specific surface area of 900-1,200m 2 /g, and the pore volume of secondary pores in 1.7-10nm diameter accounts for 50% or more of the total pore volume; preferably, wherein the average grain diameter of the small crystal size Y zeolite is 300-500nm, the relative crystallinity is 95-120%, and the pore volume of secondary pores in 1.7-10nm diameter accounts for 50-80% of the total pore volume; preferably, wherein the small crystal size Y zeolite has a lattice constant of 2.425-2.435nm and a pore volume of 0.5-0.8mL/g; and wherein the hydrogenation reaction process includes two stages of reaction that are executed sequentially, the percentage content x 1 of the active metal component in the hydrogenation catalyst used in the first stage of reaction is lower than the percentage content x 2 of the active metal component in the hydrogenation catalyst used in the second stage of reaction, and the percentage content y 1 of the small crystal size Y zeolite in the hydrogenation catalyst used in the first stage of reaction is higher than the percentage content y 2 of the small crystal size Y zeolite in the hydrogenation catalyst used in the second stage of reaction.