In this study we investigated the accelerated corrosion behavior of Fe-ion irradiated RAFM steel (SIMP) in high-temperature steam. The thickness, elementary composition, surface morphology, crystal structure and microstructure of the formed oxide films were studied. Consistent with the unirradiated sample, the oxide films of the irradiated samples consisted of an outer layer of Fe3O4, a porous inner layer of Fe-Cr spinel, and an internal oxide zone composed of (Cr, Si)2O3. The thickness of the oxide films increased with the increasing displacement damage. Compared with austenitic steels, the increase of corrosion rate of SIMP steel by displacement damage is rather moderate.