Abstract: In the cup type precipitator, Ce₂(C₂O₄)₃ was used to simulate Pu(C₂O₄)₂ for continuous precipitation experiments. Keeping other conditions unchanged, process conditions including temperature at 30.0-50.0 ℃, Ce(NO₃)₃ concentrations  of 0.084 mol/L and 0.167 mol/L, crystal seed addition ratios in the range of 0-2.0×10^-1 and seed feeding position were investigated respectively, to find out their effects on the particle size distribution and morphology of Ce₂(C₂O₄)₃ particles. When the concentration of Ce(NO₃)₃ is 0.167 mol/L at 50.0 ℃, the D50 maximum values(D50 is the value of the particle diameter at 50% in the cumulative distribution) of Ce₂(C₂O₄)₃ particles can increase by 62.2 μm compared with that without crystal seeds. When the concentration of Ce(NO₃)₃ is 0.167 mol/L and the crystal seeds are added in the peripheral vortex region and the central vortex region at 50.0 ℃, the corresponding D50 maximum values are 154.1 μm and 120.7 μm respectively. When the temperature changes from 30.0 ℃ to 50.0 ℃, the maximum value of precipitated particles D50 increases with temperature. Under various process conditions, and when D50 reaches the maximum, the shape of Ce₂(C₂O₄)₃ particles is dominated by regular flaky long strips, the proportion of fragmented and irregular flaky aggregates is small. The grain growth mode of Ce₂(C₂O₄)₃ belongs to the spiral growth mechanism, and the thickness of the single layer of grain is about 16 nm.