The invention provides an iron oxide pillar laminated manganese oxide catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) dissolving manganese salt and iron salt into water so as to prepare a mixed solution, mixing the mixed solution with an alkali liquid, and performing a coprecipitation reaction; (2) putting an oxidant solution into coprecipitate obtained in the step (1) so as to oxidize the coprecipitate; (3) performing solid-liquid separation and washing on a substance obtained in the step (2); and (4) putting a laminated manganese oxide of iron ion intercalation obtained in the step (3) into a calcining furnace, heating to 200-500 DEG C in the presence of air, calcining for 5 hours, and cooling, thereby obtaining the iron oxide pillar laminated manganese oxide catalyst. The catalyst provided by the invention is high in catalysis activity, and under the condition that the air speed is as high as 50000h<-1>, the selective catalytic reduction denitration efficiency of NH3 can be up to 100% at 100 DEG C. The 100% conversion temperature of the catalyst is reduced by 40 DEG C in comparison with that of a manganese-based composite oxide denitration catalyst prepared by using a conventional coprecipitation method.