Abstract: A qualitative analytical method of liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-QTOF-MS)was developed for identification of major constituents in process residue of tripterygium glycosides. The HPLC-QTOF-MS assay was performed on a Zorbax SB-C₁₈ column(4. 6 mm × 50 mm, 1. 8 μm)with the mobile phase consisting of acetonitrile and water containing 0. 2% formic acid in gradient mode. Positive ion mode was used for TOF-MS. According to the accurate molecular weight, MS fragment pathway, comparison with the retention time of reference compounds, total 30 compounds, including fifteen alkaloids, ten diterpenoids, four triterpenoids and an unsaturated fatty acid were identified or tentatively characterized in process residue of tripterygium glycosides. This study may be helpful to the comprehensive exploitation and utilization of process residue of tripterygium glycosides.