The invention relates to a preparation method and application of porous magnetoplumbite barium ferrite. The method takes citric acid as a complexing agent, ammonium hydroxide as a precipitator, and iron nitrate nonahydrate and barium nitrate as the raw materials, and a sol-gel method and a self-propagating combustion method are combined to prepare the porous magnetoplumbite barium ferrite. The method has the advantages that the raw materials are cheap and easy to get, the process is simple, the operation is convenient, the method is energy-saving and efficient, the homogeneity of the product is good, and the morphology is controllable; a prepared magnetoplumbite barium ferrite powder has a porous structure, is high in specific surface area and relatively good in adsorptive property, can beapplied to the absorption of pollutants in the environment field, and is easy to separate and recycle.