The present study was undertaken to evaluate and compare the potential of antioxidant activities of olive leaf extracts(OLEs) with other natural or synthetic antioxidants. So, the aim of this study was to assess the effectiveness of methanolic-,ethanolic-,and water-olive leave extracts (OLEs) and compare it with other antioxidants such as green tea extract , tert-butylhydroxyquinone (TBHQ) , citric acid on the oxidative stability of virgin canola oil during storage at an oven at 63±1°C temperature for 0,5,10,15,20 days. To follow the relative of oxidative deterioration of canola oil , oils were analyzed periodically for their peroxide value (PV) , iodine value (IV) , acid value (AV) and Thiobarbituric acid (T.B.A.). Analysis of heated canola oils demonstrated significant increases in PV and AV and T.B.A. However , IV of the oils were markedly decreased. Results also showed that olive leaf extracts (i.e.,methanolic-,ethanolic-,and water-olive leave extracts) secured protective effect against oxidation of canola oil and can serve as substitutes for synthetic antioxidants .