Antioxidants have been widely used as food additives or medicinal materials to inhibit oxidative degradation of foods or protect human cells against the effects of free radicals.Phenolic compounds are well known for their strong antioxidant and free radical scavenging ability.Interest in food phenolics has grown greatly so as to find natural antioxidants for potential application in foods or to replace synthetic antioxidants with carcinogenicity or in functional ingredients to provide beneficial effects on human health.This article offers an overview on the antioxidant activity of the main groups of polyphenolic compounds from variety of edible plants living in both terrestrial and marine environments.