Abstract: Oxalic acid has a significant catalytic effect on the fading reaction of potassium chromate oxidizing of methyl red. According to the catalytic kinetic spectrophotometric method has been developed for determination of micro oxalate acid in pure nitric acid system, the influence of Mn²⁺, UO²⁺₂ and Pu⁴⁺ on determination of oxalic acid was further investigated. The H column can eliminate the interference of metal ions in the system, and the standard recovery and precision of the method were determinate. The results show that the concentration of oxalic acid obeyes the Beer’s law in the range of 0-10.00 μmol/L and the regression equation is 1/ΔA=0.163 8c(H₂C₂O₄)+0.837 2 with the correlation coefficient r of 0.999 9. The recoveries of the studied compound are in the range of 101%-102% with the detection limit of 007 μmol/L, and the relative standard deviation are 0.76%-1.37%(n=5). The method can be used for a rapid and cost-effective alternative for determination of oxalic acid in nitric acid containing constant uranium and plutonium.