The invention discloses the method for preparation of electrochemistry nano cerium dioxide, comprising the following steps: electrolyzing and oxidating the tervalency cerium to tetravalence cerium, hydrolyzing; using cerous nitrate, ammonium nitrate and ammonial solution as raw material, confecting electrolytic solution from 0.2-0.7mol/L cerous nitrate and ammonium nitrate, using the ammonial solution to adjust PH to 5-8, using titanium base ruthenium-rhodium-iridium or tantalum- titanium- iridium composite coating as anode, using graphite as cathode, electrolyzing at 20-80Deg.C, stirring, filtration washing, drying, grinding and getting the 30-50 nanometer cerium dioxide powder. |