The purpose of this study was to evaluate the occurrence of lipid oxidation in oil extracted from peanut seeds which were treated with 3, 6 and 9 kGy of gamma irradiation and stored for 12 months. Physicochemical properties of the peanut oil were determined. The analyses were focused in the main chemical and physical constants of oil: acid value (AV), peroxide value (PV), iodine value (IV), Saponification value (SV), Thiobarbituric value (TBA), Refractive index (RI), and color values (L*, a*, b* and ï„E- values). The results indicated that the chemical properties such as IV, SV, TBA and RI of the oils extracted from gamma irradiated peanut were almost unaffected; the AV and PV increased. Color parameters L* and b* decreased (p<0.05) after irradiation, while color parameters a* and ∆E increased (p<0.05). The overall physicochemical properties values of oil extracted from peanut seed treated with 0, 3, 6 and 9 kGy and stored for 0, 6 and12 months were falls within the recommended codex for edible peanut oils.