Sunflower oil was used as environmentally friendly source to develop novel self-catalyzed waterbornepolyurethanes (WPUs) as efficient corrosion inhibitors for sour oilfield solution. A comprehensive experimentaland computational analysis was performed to evaluate the inhibition effect of WPUs. The resultsof electrochemical measurements indicated that 200 lM of WPUs were effectively protected mild steelfrom sour corrosion by 95% and 94.6% at 25 C and 60 C, respectively. Furthermore, it was found thatthe best inhibition efficiency was provided by WPU when pyrrolidine was included in its structure, particularlyat 60 C. Additionally, a smoother steel surface was observed in the presence of WPUs, indicatingthe adsorption of the polyurethane molecules on the metal surface. The results of X-ray photoelectronspectroscopy further confirmed the chemical adsorption of WPUs on the surface of mild steel. Moreover, scanning Kelvin probe microscopy revealed that the potential distribution of the steel surfacewas shifted to the negative values, which show the adsorption of the inhibitor on the surface and inhibitionof the corrosion process. Besides, high values of adsorption energy were achieved for WPUs usingmolecular dynamic simulation, indicating their spontaneous adsorption to the Fe (110) surface. The maximumadsorption energy of 794.9 kcal/mol was obtained for WPU3, which is consistent with experimentaldata. These results show that sunflower oil can be considered a potential source to developself-catalyzed polyurethanes under mild conditions as effective corrosion inhibitors for sourenvironment.