The aim of this paper was to evaluate the antioxidant properties of the different extracts from Arum dioscoridis seeds (methanolic, acetone and hexane extracts) and to correlate their antioxidant potential to the composition of phenolic compounds. The scavenging ability of free radicals was measured using β-carotene-linoleic acid model system and 2,2-diphenyl-1-picrylhydrazyl (DPPH·) analysis and the IC 50 values of the extracts were also determined. The methanolic extract of A. dioscoridis seeds showed greater antioxidant activity than acetone and hexane extracts by β-carotene-linoleic acid model system and DPPH· analysis, respectively. Qualitative and quantitative analyses of major phenolic compounds were also performed. The main antioxidant compound from the methanol extract was found to be vitexin. Other identified phenolics in all extracts that are likely to contribute to the antioxidant potential are: ferulic acid, naringin, eriodictyol and p-coumaric acid. © 2011 Wiley Periodicals, Inc.