Cashew Nut Shell Liquid (CNSL) has been tested as a corrosion inhibitor for carbon steel in 3% aqueous NaCl solution (pH 6) saturated with carbon dioxide gas at 30°C under static conditions using ac-impedance and potentiodynamic polarisation techniques. It was found that CNSL reduces the extent of the electrochemical processes taking place on carbon steel undergoing corrosion. The corrosion rate of the carbon steel was reduced by over 92 % when only 300 ppm of CNSL was applied. This indicates that CNSL is a potential corrosion inhibitor for carbon steels in CO2 environment.