Sanggenol P (1), a new isoprenylated flavonoid, together with nine known ones, cyclomorusin (2), morusin (3), mulberrofuran G (4), sanggenol A (5), sanggenol L (6), sanggenol N (7), cyclomulberrin (8), cyclocommunol (9) and ursolic acid (10) was isolated from Morus alba L. Sanggenol P (1) was characterized based on extensive IR, UV, 1D and 2D NMR spectroscopic analysis. Compounds 5, 6, 7 and 9 were obtained from this plant for the first time.