The invention relates to a high-purity
ginkgo flavone and a composition thereof. The high-purity
ginkgo flavone is light brownish yellow, and tastes slightly bitter; the content of
ginkgo flavone is greater than or equal to 50%, the peak ratio of
quercetin to
kaempferol is 0.8-1.2, the peak ratio of
isorhamnetin to
quercetin is greater than or equal to 0.15, the concentration of ginkgoic acid is smaller than 5ppm, and the content of residue on ignition is smaller than 0.8%. The
water content is smaller than 5.0%. The method for preparing the high-purity ginkgo flavone comprises the following steps: extracting by heating ginkgo leaves, which are used as the
raw material, under
reflux with a 20-80 wt%
ethanol solution; concentrating the extracting solution to recover
ethanol; separating by passing through
macroporous resin columns; carrying out
ethanol desorption; diluting the product by adding water; adsorbing by passing the product through a gel-type
hydrogen bond adsorption resin which is mainly based on
hydrogen bond adsorption, and desorbing; and collecting the
effluent liquid and the
desorption liquid, concentrating and
drying. The preparation technique is simple and reliable, has the
advantage of low cost, and does not use toxic organic solvents in the process, thereby being environment-friendly. The high-purity ginkgo flavone can be made into a composition as an effective constituent, and the composition can be used as various preparations (capsules, tablets, oral liquids, granules,
powder, injections and the like) of ginkgo flavone medicines or health products.