The controlled dissolution on the corrosion of Al-Si Ccomposites in sea water (3. 5% NaCl) has been investigated using Mass loss, Gasometric measurements, Current-Potential measurements and Impedance studies in the presence and absence of Cefalotin (CFLN) as green inhibitor. This study has confirmed that the compound retarded the dissolution of Al-SiC in sea water environment by acting as mixed inhibitor. Diffused reflectance spectra confirmed the formation of adsorbed film of inhibitor on metal. The adsorption of the compound on composite surface followed Temkin’s adsorption isotherm. The quantum chemical analysis validates the inhibition action of the green inhibitor determined by electrochemical methods. © 2015, International Journal of ChemTech Research. All right reserved.