Abstract: OBJECTIVE To improve the method for the examination of related substances in pantoprazole sodium for injection and establish an HPLC-Q-TOF-MS method for the structure determination of the degradation impurities. METHODS The analysis was performed on Waters Symmetry C₁₈(250 mm×4.6 mm, 5 μm) with the mobile phase consisting of 10 mmol·L^-1 ammonium acetate (adjusted to pH 4.5 by acetic acid)-acetonitrile in gradient mode. The detection wavelength was 289 nm and the flow rate was 1.0 mL·min^-1. The compound was ionized in the electrospray ionization(ESI) and operated in positive mode. RESULTS The improved method for the examination of related substances could separate the major degradation impurities effectively. According to the mass spectrum and high resolution data of degradation impurities in pantoprazole sodiu the structure of four degration impurities could be infered. CONCLUSION The chromatographic condition can detect the related substances in pantoprazole sodium for injection effectively. And the structure identification of the degradation impurities can provide technical support for stability study of this medicine.