The invention belongs to the technical field of catalysis, and relates to a preparation method of a catalyst carrier for preparing natural gas from coke-oven gas. The preparation method comprises the following steps: neutralizing a soluble salt solution of magnesium by using an alkali, washing the above obtained precipitate until the precipitate is qualified, adding alkali earth oxide, rare earth metal nitrate and gamma-Al2O3, mixing and beating above materials, filtering the obtained mixture, drying the filtered mixture, roasting the dried mixture, granulating the roasted mixture, carrying out pressing molding, and roasting the molded mixture to obtain the catalyst carrier The carrier has good hydrothermal stability, and a methane synthesis catalyst prepared by using the carrier is suitable for a methanation reaction for preparing natural gas from C2 hydrocarbon-containing coke-oven gas and realizes difficult carbon deposition at high CO content.