The influence of cetyl trimethyl ammonium bromide (CTAB) on the corrosion of carbon steel in HCl and H2SO4 solutions has been studied using several techniques such as weight loss, Tafel polarization, linear polarization and open circuit potential. Inhibition efficiencies have been obtaining from weight loss measurement, the effect of temperature on corrosion inhibition and the effectiveness of the inhibitor at higher acid strength have been examined. Polarization studies reveal that the inhibitor behaves as an effective inhibitor in H2SO4 as well as in HCl solutions. Measurements of values of polarization resistance (Rp) have also been carried out. The open circuit potential curves was shifted to less negative potential contrary to the blank. (C) 2002 Elsevier Science B.V. All rights reserved.