The invention belongs to the technical field of core-shell type metal oxides, in particular to a core-shell type MnO2@TiO2 catalyst as well as a preparation method and application. The method comprises the two steps of preparing a core material MnO2 and preparing MnO2@TiO2. The core-shell type catalyst with titanium dioxide coated onto manganese dioxide prepared by the invention is very high in catalytic activity, free from toxicity and good in stability when being applied to a selective catalytic reduction denitration technology. The resistance of the catalyst to sulfur dioxide is improved, and the recycling times of the catalyst are increased.