Antioxidant activity of methanolic (50%) extracts of olive pulp (Olea europaea L.) was investigated.Total antioxidant activity,phenolic contents and reducing power in 6 Iranian olive cultivars were determined.The highest antioxidant activity (28.699 mmol FeⅡ/100g dry plant),total phenolic contents (2997 mg gallic acid/100g dry plant) and reducing power (8.331 g Vitamin E/100g dry plant) were detected in Michen and the lowest in Conservalina.A linear positive relationship existed between the antioxidant activity,total phenolic compound (r2=0.976) and reducing power of the tested olive pulp (r2=0.848).Iranian olives possess relatively high antioxidant activity due to contribution of phenolic compounds.The present study showed that Iranian olive cultivars are strong radical scavengers and can be considered as good sources of natural antioxidants for medicinal and commercial uses.