Abstract: H₂⁺ ions were implanted into ilmenite at room temperature, and the microreaction mechanism during the reduction of ilmenite was investigated by transmission electron microscopy. The results indicate that during the course of reduction, metallic iron with110 orientation is formed on ilmenite along1431 direction, (222) or (222) plane of iron is transformed from (4264) or (4264) plane of ilmenite firstly. The structure change during the course of reduction from ilmenite to iron is a gradually changing process.