The anti corrosion behaviour of Argan Oil (AO) and Cosmetic Argan Oil (CAO); extracted from Argania spinosa (L); in 2M H3PO4 containing 3.10-1 M NaCl solution on copper has been examined and characterized by weight loss, Tafel polarization, electrochemical impedance spectroscopy (EIS) . The experimental results reveal that the oils were shown to have good inhibition efficiencies in phosphoric acid. EIS analysis revealed that increase in concentration increases the charge transfer resistance, thus increased inhibition efficiency. Potentiodynamic polarization studies showed the oils acted as a mixed-type of inhibitors. The adsorption mechanisms for both extracts were mainly physisorption. The results obtained from the various methods are in good agreement.