Nowadays, in studies show that plants are rich in antioxidant such as carotenoids, pigments, phenols and flavonoids. Therefore. the present study was designed to evaluate the free radical scavenging activity and antioxidant content of methanol extract of leaf and fruit of Linum arboreum L. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azinobis (3-etil-bezotiazolin 6 sulfonat) (ABTS) radical scavenging activity, reducing power, total antioxidant, total phenolic and total flavonoid assay were carried out to evaluate the antioxidant potential of the methanolic extracts. The IC50 values were calculated for the DPPH and ARTS assays in order to evaluate the antioxidant efficiency of each of the L. arboreum extracts. According to our results. IC50 values for DPPH were 106.55 +/- 1.20 mu g ml(-1) and 108.56 +/- 2.65 mu g ml(-1) while IC50 values for ARTS were 1144.8 +/- 38.44 mu g ml(-1) and 1114.7 +/- 37.09 mu g ml(-1) for the leaf and fruit extracts. respectively. Free radical scavenging activity of leaf and fruit extracts did not differ significantly from each other. However, leaf extract showed a significantly greater total flavonoid and total antioxidant contents compared to fruit extract. As a result, L. arboreum could be considered as a potential source of natural antioxidant.