The invention relates to the coating field, and particularly discloses a water-based anticorrosive coating and a preparation method thereof. The water-based anticorrosive coating comprises a component A and a component B. The component A comprises the following components by mass: 15-25 parts of a water-based isocyanate curing agent, 15-55 parts of zinc powder, 1-5 parts of a defoaming agent, 1-5 parts of a wetting dispersing agent, 0.9-2 parts of an anti-sinking thixotropic agent, 0.1-5 parts of a conductive macromolecule/fullerene composite material, 0.5-1 part of a flash-rust resistant agent, 0.5-1 part of a flatting agent, 1-3.5 parts of an adhesive force accelerant, and 5-15 parts of a rust resisting pigment; and the component B comprises the following components by mass: 5-13 parts of methyl methacrylate, 15-25 parts of butyl acrylate, 7-16 parts of styrene, 15-30 parts of an epoxy resin, 1-6 parts of a methacrylic acid, 1-5 parts of acrylamide, 1.5-2 parts of hydroxyethyl acrylate, 0.5-5 parts of an emulgator, 0.5-5 parts of an initiator, 80-130 parts of deionized water, and 0.1-1 part of ammonia water. The water-based anticorrosive coating is prepared by stirring and mixing the prepared component A and component B according to the mass ratio of 8-16:1, and has the advantages of strong shielding property, excellent corrosion resistance, environmental protection, good flexibility and strong adhesive force.