The invention discloses a preparation method of anti-oxidation water-based magnetorheological main dispersed particles, and belongs to the technical field of magnetorheological material preparation. By aiming at the problem of decrease of the working efficiency, even a failure of a magnetorheological device usually caused by poor oxidation resistance of the existing prepared water-based magnetorheological fluid in application, chlorogenic acid in leaves of chrysanthemums is extracted, and grafted with aspartic acid, because the chlorogenic acid has chelating groups, the chelating groups and chelation bonds are firmly coated on the surfaces of hydroxy iron powder particles through chemical adsorption after in graft copolymerization with amino acid by being used as anchoring groups to form a dense organic protective layer to effectively improve the oxidation resistance of the magnetorheological main dispersed particles, the magnetic-induced shear stress of the water-based magnetorheological main dispersed particles prepared by the invention is decreased by 15% after being in a nitric acid solution of which the concentration is 0.002mol/L for 3 hours, and compared with the ordinary water-based magnetorheological fluid, the oxidation resistance is improved by 45 to 50%, and the preparation method of the anti-oxidation water-based magnetorheological main dispersed particles disclosed by the invention is simple in preparation steps and safe, and pollution-free.