AbstractIn this study, a self‐healing nanocomposite hydrogel (NC hydrogel) loaded with sodium citrate (SC) corrosion inhibitor was developed. NC hydrogels were synthesized through free‐radical polymerization of N, N’‐Dimethylacrylamide (DMA) within a dispersion of silica nanoparticles. FT‐IR, SEM and TGA were applied to evaluate the loading of SC, self‐healing test was used to confirm the self‐healing capability of NC hydrogel. NC hydrogels were coated on the surfaces of Q235 steel, the exposure test results suggest that the corrosion protection of NC hydrogel improves with the loading of SC. Macro, micro morphologies prove that with the releasing of SC, a layer of adsorptive film was formed on the steel surface to prohibit the corrosion of carbon steel. Electrochemical results signify that NC (0.9 wt.% SC) hydrogel possesses the optimum corrosion resistance. The authors consider that as carrier, NC hydrogel can fulfill better corrosion inhibitive action of SC, meanwhile, effectively provide corrosion protection for carbon steel.