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Graphene is a particular type of material, made of a single crystal lattice layer of two dimensional honey-comb structure with excellent electrical, thermal and mechanical properties. Graphene oxide (GO) has been subjected to several studies in recent years. One of its possible applications concerns the production of composite coatings, to improve the protective properties of the coating itself together with other functional properties such as a remarkable conductivity. The cataphoretic electrodeposition process allows to obtain a coating with uniform thickness also with complex geometry, good adhesion properties, in a simple and economic way. To get good properties it is important to have a uniform distribution of graphene flakes, avoiding cluster formation, together with good adhesion between graphene particles and organic matrix. In this work, the effect of the graphene flakes addition in the organic coating was studied. The graphene flakes have been subjected to nitric acid oxidation treatment and functionalized with organosilane, to get a good dispersion in the acrylic cataphoretic bath. The deposits’ morphology was observed under optical and electronic microscope, to study the possible defectiveness of the coatings. The corrosion protection properties were evaluated by salt spray exposure test following the ASTM B117 standard and by electrochemical impedance spectroscopy measurements in chloride solution. The process parameters, as well as the concentration of functionalized graphene oxide inside the cataphoretic bath, have been optimized, obtaining composite coatings with excellent corrosion resistance properties. It has been verified that the presence of graphene in the cataphoretic coating allows to obtain a better behavior in an aggressive environment and corrosion protection of the metallic substrate. Finally, deposit conductivity was measured following ASTM D 257-07 standard.