Abstract: The reaction of hydrazine and its derivative with ammonium metavanadate may produce hydrazoic acid(HN₃). A single column ion chromatography is used for the determination of HN₃ after neutralizing the rest acid in the sample with sodium hydroxide. Chromatography separation of HN₃ is carried out on a 25 cm×0.46 cm (inside diameter) stainless steel column packed with Vydac IC302 ion Chromatography packing. The eluent is 1 mmol/L o-phthatic acid, and the ion is detected by conductivity detector. The detection limit in the presence chromatography is 5 μg/mL, the linear range is from 5 to 201 μg/mL, the linear correlation coefficient is 0.999 4, respectively. The analysis accuracy is 2% for standard sample, and the detection limit is 51 μg/mL for HN₃ in the real sample.