Abstract:High quality manganous-manganic oxide (Mn3O4) was prepared from manganese chloride solution purified with N235 extraction. The results show that the optimum conditions include reaction temperature of 60 ℃, stirring speed of 500 r/min, dosage of ammonium chloride of 2 g/L, manganese concentration of 20 g/L, pH=7.5, solution flow rate of 3 L/h, and oxidation time of 6 h. The prepared Mn3O4 reaches the advanced level of domestic electronic grade with concentrated grain size, larger specific surface area and lower content of calcium and magnesium. The impurity contents (iron, selenium, chromium) are far below those of the counterpart in domestic market.