Abstract: Using high performance liquid chromatography-mass spectrometry(HPLC-MS/MS) technology, the components in the water extract of loquat leaves were analyzed, and the terpenoids were analyzed. Using a C₁₈ column (2.1 mm×100 mm, 1.8 μm), using water +0.1% formic acid solution as mobile phase gradient elution, using ESI ion source, collecting mass spectrometry data in positive and negative ion modes, a total of 120 compounds were detected ; Including 18 kinds of terpenoids with a total relative content of 1452.693 μg/mL; 24 kinds of flavonoids with a total relative content of 10378.081 μg/mL; 18 kinds of phenolic compounds with a total relative content of 36967.955 μg/mL; 5 kinds of coumarins compounds with a total relative content of 214.778 μg/mL; The structures of 18 terpenoids were further identified, including 6 ursane type, 7 oleanane type, 3 sesquiterpenes, and 1 diterpenoid. And a special iridoid glycosides; Roburic acid, ginkgolide B, prespatane, shanzhiside methyl ester, icariside B_5, quillaic acid, asiatic acid, 18β-glycyrrhetinic acid were no report in the previous active substances of loquat leaves. This article provides a reference for the research on the water-extracted components of loquat leaves.