PURPOSE: To obtain a lipid metabolism improver comprising hesperetin and/or naringenin as an active ingredient.

CONSTITUTION: This lipid metabolism improver comprises hesperetin of formula I and naringenin of formula II as active ingredients and is administered as it is or 10-95% of as the lipid metabolism improver by containing its 10-95% in a medicine carrier based on the all components. The compound of formula I and that of formula II have each a lowering action on cholesterol in blood and are effective for treating and preventing especially hypercholesterolemia, arteriosclerosis and cardiac infarction. The lipid metabolism improver can be administered orally, interstitially, percutaneously or per rectum and preferably orally. A daily dose is 0.01-50g, preferably 0.1-1g per adult. The compounds of formula I and formula II are well-known and the compound of formula I is extracted from periderm of a citrus fruit such as tangerine or orange and the compound of formula II from periderm of Citrus natudaidai, grape fruit, etc.