The partitioning of americium and neodymium by precipitation with oxalic acid was investigated in the simulated radwaste, which was composed of 10 elements of alkali, akaline earth, and transition metals in nitric acid solution. The effect of concentrations of oxalic acid and nitric acid in the simulated waste on the precipitation yield and purity of Nd and Am was examined in this study. As a result, the precipitated fraction of each element was increased with increasing concentration of oxalic acid and decreasing concentration of nitric acid. At an initial concentration of 0.5 M nitric acid and 0.5 M oxalic acid, both Am3 and Nd3+ were precipitated over 99% and other elements almost remained in the simulated solution. It was also found that Am was completely coprecipitated with Nd-oxalate precipitates, and Zr4- caused the coprecipitation of Cs2, Sr2+, and Pd2+.