Schiff base metal complexes of different stoichiometries and modes of interactions were synthesized and characterized using different metals Mn, Co, Ni, Cu by elemental analysis, spectral (IR and UV–Vis) methods and magnetic susceptibility studies. Electrochemical studies were performed for some of Schiff base complexes (Cu-salpr, Cu-salen, and Cu-salph·H₂O) and of H₂-salen and its corresponding Ni, Co, and Cu complexes on the corrosion behaviour of steel in 1 M sulphuric acid solution and were studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The stoichiometry of Fe and Mn (salen, salpr and salph) complex was studied by using different spectrophotometric methods.