Preparation method of micron-submicron-scale rare earth oxide powder

The invention discloses a preparation method of micron-submicron-scale rare earth oxide powder. The preparation method includes: dissolving rare earth oxide in an acid to prepare a rare earth salt solution; subjecting the rare earth saline solution and an oxalic acid precipitant to precipitation reaction to obtain rare earth oxalate powder; drying the rare earth oxalate powder; utilizing an air flow mill for breaking and grading to obtain rare earth oxalate powder with central granularity at nanoscale; firing the rare earth oxalate powder to obtain rare earth oxide powder with central granularity at micron-submicron-scale. In the production process of the preparation method, operation is easy to control, the preparation method is simple, and the rare earth oxide powder prepared by the method is high in granularity, uniform in distribution, high in dispersity, low in cost and easy for industrial production, and the air flow mill can be further improved to reduce non-rare-earth impurities introduced in the production process.