1-(4-Nitrophenylo-imino)-1-(phenylhydrazono)-propan-2-one (NO(2)AM) was studied as a corrosion inhibitor for mild steel in 1 M HCl solution by weight loss, polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and UV-visible spectroscopy. The inhibition efficiency was found to increase with increasing inhibitor concentration and to decrease with increasing temperature. Some thermodynamic and kinetic parameters were calculated and discussed. The adsorption of the inhibitor on the mild steel surface obeyed the Langmuir adsorption isotherm. Polarization studies showed that the inhibitor behaves as a mixed-type inhibitor. SEM was performed for surface analysis of the uninhibited and inhibited mild steel samples. The density functional theory (DFF) was employed for theoretical calculations. The results obtained from experimental measurements and those from theoretical calculations are in good agreement.