A high performance liquid chromatography to analyze 3, 3′-diamino-4, 4′-azoxyfurazan(DAOAF) was established and characterization of impurities trapped in the DAOAF product was carried out by MS. Results show that the chromatographic conditions after optimization are: chromatographic column, ZorbaxSB-C18(250 mm×4.6 mm, 5.0 μm) column; mobile phase, acetonitrile/water (V:V=40:60); flow rate, 0.8 mL·min^-1; column temperature, 25 ℃; wavelength, 230nm; injection volume, 10 μL. Under the optimized chromatographic conditions, DAOAF and impurities in DAOAF are effectively separated. The calibration curves of DAOAF within the mass concentration of 10.02-100.20 mg·L^-1 have good linearity with the linear correlation coefficient of 0.9990. The main impurities in DAOAF are diaminoglyoxime, 3, 4-diaminofurazan and 3, 3′-diamino-4, 4′-azofurazan. The method has high sensitivity and good reproducibility, can be used for the determination of the related substances in the product of DAOAF.