The corrosion of sintered and sintered-plasma nitrided steels containing different alloying elements was evaluated through analysis of the potentiodynamic polarization curves of the samples at pH=7, with 1.25 M KNO3 as electrolyte. The Fe-3.0% Ni and Fe-0.1% C sintered alloys show better performance in relation to electrochemical corrosion, than sintered pure iron samples. In addition, Fe-4.0% Mn, Fe-1.5% Mo and Fe-1.5% Si alloys exhibited increased anodic current densities in relation to the pure iron sample. After the nitriding process the anodic current densities of all samples containing an alloying element were considerably diminished. The sintered-nitrided pure iron sample was the only nitrided part whose current density was higher than the current density of the non-nitrided sample.