Abstract:Nine constituents have been isolated from the bud of Cleistocalyx operculatus (Roxb.) Merr. et perry (after the removal of essential oils by steam distillation), eight of them were identified as 2‘, 4‘-dihydroxy-6‘-methoxy-3‘,5‘-dimethylchalcone (Ⅲ), 5,7-dihydroxy-6,8-dimethylflavanone (Ⅳ), 7-hydroxy-5-methoxy-6,8-dirnethylflavanone (Ⅴ), ethyl gallate （Ⅰ）, gallic acid, (Ⅱ), ursolic acid‘ (Ⅵ), β-sitosterol (Ⅷ) and cinnamic acid (Ⅶ), based on the evidences from spectroscopic (UV, IR, NMR, MS) analysis and comparison of physico-chemicat constants. The identification of the ninth constituent is under way.