Electrochemical investigations were carried out to study the corrosion behaviour of tin plate in citric acid, in the absence and presence of various concentrations of amino acids, namely arginine monohydrochloride, lysine monohydrochloride, cysteine and methionine, by using potentiodynamic polarization technique. The results of this investigation revealed that nitrogen containing amino acids gave inhibition efficiency (113) >70% at 5 ppm and sulphur containing amino acids gave IE of 69% and 56% respectively at concentration of 50 ppm.