The aim of this study was to examine the application of ionizing radiation in order to improve the protective properties of a self-organizing monolayer of elaidic acid as a corrosion inhibitor on copper samples. SAMs are often used as corrosion inhibitors, due to their simple adsorption on the metal surface. In this work, the coating was applied by immersion in a solution of elaidic acid. Gamma radiation was applied to achieve crosslinking of the coatings and to improve their protective properties. The samples were irradiated in three different media: water, ethanol and air. The influence of gamma radiation was studied by electrochemical methods (Tafel extrapolation and electrochemical impedance spectroscopy), contact angle measurements and FTIR analysis. In water as an irradiation medium the effect of purging the solution with nitrogen and nitric(I)oxide gases, both of which serve to remove oxygen from the system, was compared, while N2O additionally formed radicals which promote crosslinking of the coating. In water previously purged with nitrogen, the samples were irradiated in a apsorbed dose range of 5-60 kGy. According to the obtained results, in the range of 20-60 kGy the crosslinked SAM of elaidic acid provides a certain improvement of efficiency compared to the nonirradiated SAM, but the highest improvement is shown on the samples irradiated with 40 kGy (41.6%). The samples irradiated with 40 kGy in water previously purged with N2O show even greater improvement of efficiency, due to the greater effect on the crosslinking of the applied SAM (58.7%). The highest improvement of protection efficiency and degree of crosslinking is shown by the sample irradiated with 110 kGy in air (63.5%). Samples in ethanol were irradiated in the range of 0.5–110 kGy, but an increase in the effectiveness of the protective properties was not achieved in comparation with the non-irradiated samples.