Provided is a graphene-based coating suspension comprising multiple graphene sheets, thin film coating of an anti-corrosive pigment or sacrificial metal deposited on graphene sheets, and a binder resin dissolved or dispersed in a liquid medium, wherein the multiple graphene sheets contain single-layer or few-layer graphene sheets selected from a pristine graphene material having essentially zero % of non-carbon elements, or a non-pristine graphene material having 0.001% to 47% by weight of non-carbon elements wherein the non-pristine graphene is selected from graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, doped graphene, chemically functionalized graphene, or a combination thereof. The invention also provides a process for producing this coating suspension. Also provided is an object or structure coated at least in part with such a coating.