The invention belongs to the technical field of preparation of metal anticorrosive coatings, and in particular relates to a lignin/graphene-based composite anticorrosive coating and a preparation method and application of the lignin/graphene-based composite anticorrosive coating. The method comprises the following steps: mixing a hydroxylated lignin solution with graphite, ultrasonically strippingto prepare saturated lignin/graphene dispersion liquid, and then mixing with epoxy resin, a waterborne curing agent and a solvent to prepare the lignin/graphene-based composite anticorrosive coating.The method adopts a renewable biomass material, namely lignin, and the hydroxylation, amphiphilicity of the lignin and the Pi-Pi interaction of the lignin with graphene are used, so that hydrophobicgraphene can be uniformly dispersed in the waterborne epoxy resin to obtain the coating, and the graphene of the coating can block intrusion of small corrosive molecules layer by layer to greatly reduce corrosion paths of the small molecules, so as to delay the corrosion rate of a substrate. Furthermore, the coating further has good thermal stability and shows better capacitance arc and higher pyrolysis temperature while used for anticorrosion of metal and building material surfaces.