The invention provides a high-temperature high-selectivity carbon dioxide methanation catalyst and a preparation method of the catalyst. The preparation method comprises the steps of performing improvement based on a traditional impregnation method, preparing a magnesia alumina spinel carrier by a hydrothermal synthesis method, taking nickel nitrate as impregnation liquid, uniformly loading a nickel-bearing component to the carrier, and performing pickling treatment on an impregnated catalyst precursor to achieve egg-yellow-shaped distribution of nickel oxide on the carrier. Hydrogen is small in molecule and large in diffusion coefficient, so that diffusion into the catalyst is more facilitated, and a hydrogen-carbon ratio in the catalyst is increased; increase of the hydrogen-carbon ratio can obviously improve the selectivity of the catalyst; and an H2 conversion rate of the prepared carbon dioxide methanation catalyst can still reach above 58% under 600 DEG C and normal pressure evaluation conditions when H2/CO2 is equal to 1.