The invention relates to a non-homogeneous-phase Fenton catalyst with magnetism. The non-homogeneous-phase Fenton catalyst is a nuclear shell type microsphere Fe3O4@rGO@TiO2 of a three-layer structure. The submicron-level Fe3O4 microsphere serves as the inner core, the outmost layer is TiO2 small nanometer particles, and the Fe3O4 microsphere and the TiO2 small nanometer particles are bonded together through an rGO layer with the thickness ranging from 2 nm to 5 nm. The Fe3O4 microsphere is formed by stacking Fe3O4 small nanometer particles with the grain size ranging from 15 nm to 30 nm, and the microsphere grain size ranges from 300 nm to 400 nm. The grain size of the TiO2 small nanometer particles ranges from 5 nm to 15 nm. The non-homogeneous-phase Fenton catalyst is prepared in a neutral environment or Fenton reaction is conducted, the dissolution and losses of ferric salt are greatly reduced, efficient recycling of the catalyst is achieved, and meanwhile multi-time repeated use of the catalyst is guaranteed; the catalyst has good superparamagnetism, the magnetic response performance is excellent, and the catalyst is easy to recycle and can be separated completely within about 30 s under the action of an external magnetic field; the utilization rate of visible light is increased; furthermore, the material surface energy is lowered, the catalyst is not prone to agglomeration, dispersity is maintained, and thus the utilization rate of the catalyst is increased.