Disclosed is a stable and safe antioxidant composition which can be used routinely. Specifically disclosed is an antioxidant composition which contains one or more compounds selected from the group consisting of D-aspartic acid, derivatives and/or salts thereof. The composition may be used for the purpose of suppressing and/or improving skin conditions. The skin conditions may include, but is not limited to, fine wrinkles, a rough skin, a dry skin, a skin cancer, a skin allergy, an inflammation of the skin and a photosensitive dermatosis. The composition may be used for an external preparation for the skin, a food, and a pharmaceutical product for cataract.