New experimental data on the corrosion behavior of the 12X18H10T austenitic steel elastically strained cou-pons after 500 h long exposure in situ the NSC KIPT “Electron Irradiation Test Facility” supercritical water circula-tion loop are presented and discussed. The γ-activation analysis based computational dosimetry of samples is corre-lated to their weight gain/loss measurement data. The absorbed dose and stress effect on their irradiation assisted general corrosion is revealed. The corrosion surface/layer chemistry/microstructure are discussed with special em-phasis of the irradiation/stress impact on the protective coating stability, intergranular corrosion and precursors of cracking.