Flavonoids are a kind of compounds, whose basic nucleus has two benzene rings connected by a central three-carbon chain. It is named because there are ketone groups in the molecule and it is yellow. It is a pigment in plants, and we use it to dye. It was later found to have medicinal value. There are many plants containing flavonoids, such as Ginkgo biloba, Sophora japonica and Pueraria lobata. Various flavonoids have different effects, but they have more effects on cardiovascular and cerebrovascular diseases. Total flavonoids of Ginkgo biloba leaves are sold in the market, and rutin tablets are also very common, which have the effect of increasing vascular toughness and are auxiliary drugs for hypertension to prevent vascular rupture caused by long-term hypertension.