The invention discloses one-component room-temperature curing water-based anticorrosive resin and a preparation method thereof, and relates to the technical field of anticorrosive coating. The anticorrosive resin comprises unsaturated fatty acid, epoxy resin, vinyl monomers, acrylic monomers, acrylate monomers, ethyl orthosilicate and perfluorosilane. The preparation method of the resin comprisesthe steps that unsaturated fatty acid and epoxy resin are subjected to an esterifying reaction to generate epoxy ester, the vinyl monomers, the acrylic monomers, the acrylate monomers and initiators are uniformly mixed and then added dropwise to epoxy ester for a reaction, heat preservation is conducted for a certain period of time, then ethyl orthosilicate is added for a reaction, a neutralization agent is adopted for neutralization, perfluorosilane is added, and finally water is added for high-speed dispersion. According to the resin, with ethyl orthosilicate and perfluorosilane as special functional cross-linking agents, the cross-linking agents are not simply self-polymerized, further cross-linking polymerization can be generated between ethyl orthosilicate and perfluorosilane after orbefore polycondensation, and the corrosion resistance, heat resistance, water whitening resistance and neutral salt spray resistance of coating film are improved.