Based on ion chromatography technology, we have developed a new method that combines ion chromatography with a conductivity detector to separate and determine the substances of oxalic acid and glyoxalic acid, which are the main substances in the electrosynthesis of glyoxalic acid. The experimental results demonstrate that the detection sensitivity is ahead of 10 -6 grade, the cofficient of variation of retention time, the height of peak and the area of peak outperform 1%. All the recoveries of the detected substances are ranged between 98% and 102%. The method exhibits advantages of high selectivity, sensitivity, speediness and simple equipment. Furthermore, simultaneous determination of a mixture of several substances can be carried out by the method. We have demonstrated in the current paper that the ion chromatography is a speedy, effective, new detection method, which may be used to determine the substances existing in the electrosynthesis process of glyoxalic acid.