The invention discloses a catalyst applied to reaction for synthesizing parachloroaniline through hydrogenation. The catalyst comprises a magnetic core, a microporous zirconium dioxide layer covering the magnetic core and platinum nanoparticles loaded on the microporous zirconium dioxide layer. The catalyst takes magnetic particles as the core; the magnetic particles are adsorbed and separated by magnets and are convenient to collect and reuse; the platinum nanoparticles are loaded on the microporous zirconium dioxide layer; the microporous zirconium dioxide layer is taken as a carrier and is capable of effectively improving the dispersity of active components and promoting the catalytic activity of the platinum. Meanwhile, the invention also provides a preparation method of the catalyst. The preparation method is simple and controllable; the catalyst prepared by the method is adjustable in structure and components and high in catalytic activity; when the catalyst is applied to the reactions such as the reaction for synthesizing parachloroaniline through hydrogenation, the reaction selectivity and the target product yield can be greatly improved.