7 flavonoids are isolated from the leaves of Hovenia acerba Lindl. On the basis of chemical and spectralmethods (IR,1H,13 CNMR),they are ivdentified as kaempferol(Ⅱ),quercetin(Ⅱ),isoquercetin(Ⅳ),kaempferol-3-Oa-L-rhamnopyranosyl(1)-?-D-galactopyranoside(Ⅶ),kaempferol-3-O-rutinoside(Ⅶ),quercetin-3-O-?-L-rhamnopyranosyl(1→6)-?-D-galactopyanoside(Ⅹ Ⅸ),and rutin(Ⅸ),All of them are isolated for the first time from genus Hovenia.