Abstract: The inhibition of steel-copper couple galvanic corrosion in petroleum waste water solution by Ziziyphus leaves extract was studied at different temperature and different cathode to anode area ratio using weight loss technique. Inhibition efficiency increases with increase in inhibitor concentration but decrease with rise in temperature. Maximum inhibitor efficiency was around 90%. The adsorption behavior of Ziziyphus leaves extract obeyed the Langmuir adsorption isotherm while the effect of temperature was according to Arrhenius Model.