The present invention relates to a method for stabilizing reduced coenzyme Q10, which is useful as an ingredient in good foods, functional nutritive foods, specific health foods, nutritional supplements, nutrients, animal drugs, drinks, feeds, cosmetics, medicines, remedies, preventive drugs, etc., and to a composition therefor. The composition comprises reduced coenzyme Q10, a fat and oil (excluding olive oil) and/or a polyol, and doesn't substantially inhibit the stabilization of reduced coenzyme Q10. Additionally, the composition is a reduced coenzyme Q10-containing composition which comprises reduced coenzyme Q10, a polyglycerol fatty acid ester, and a fat and oil and/or a polyol.
