The novel inhibitive effect of N-(4-aminosulphaacetamide) on the corrosion of Al-SiC composites in 1N HCl has been investigated using weight loss, gasometric measurements, potentiodynamic polarization and impedance studies. This study clearly indicated that the compound acted as cathodic inhibitor. Diffused reflectance spectra confirmed the formation of adsorbed film of inhibitor on metal. The adsorption of the compound on composite surface obeyed Temkin's adsorption isotherm. The quantum chemical analysis substantiates the inhibition efficiency of the compound determined by electrochemical methods. © 2013 University of Manchester and the authors.