<p>Recrystallized ODS steel PM2000 was irradiated with 3.5-MeV Fe¹³⁺ ions at 700 °C to a displacement damage of 0.82 dpa to study the change of dispersoids in the steel under the irradiation. Dispersoids in the thin-foil specimens of the recrystallized steel before and after the irradiation were observed and analyzed using transmission electron microscopy and energy dispersive X-ray spectrometry. The YAlO₃, Al₂Y₄O₉, YCrO₃, and TiC phases pre-existing in the recrystallized steel remained in the irradiated steel. The irradiation caused a large change in the nature of dispersoids. After the irradiation, a greater number of finer particles were densely dispersed throughout the matrix, and three types of irradiation-induced phases were observed and identified in the irradiated steel. These irradiation-induced phases were Y₂O₃, having a simple monoclinic lattice, Al₂Ti₇O₁₅, with a base-centered monoclinic lattice, and Al₂Fe₅O₁₂, with an FCC lattice. The precipitation of carbides and intermetallic compounds occurred in the steel during the irradiation. They were identified to be Cr-rich M₇C₃ and M₃C₂ with the same simple orthorhombic lattice and Fe-Cr with a BCC lattice. The formation of these irradiation-induced phases in addition to the carbides and intermetallic compound is also discussed.</p>