A composition having an antioxidative activity, especially, having a sufficient activity for removing active oxygen and/or free radicals is provided. The composition includes both reduced coenzyme Q 10 and a carotenoid, and the activity for removing active oxygen and/or free radicals is synergistically enhanced. A method for removing active oxygen and/or free radicals by using the composition containing both reduced coenzyme Q 10 and a carotenoid is also provided.