The effect of phosphate (PO43-), chromate (CrO42-), molybedate (Mo-4(2-)) and nitrite (NO2-) ions on the pitting corrosion of steel in 0.1 M NaCl solution has been studied using potentiodynamic polarization and SEM techniques. The addition of increasing concentrations of PO43-, CrO42-, MoO42- and NO2- anions causes a shift of the pitting potential (E-pit) in the positive direction, indicating the inhibitive effect of the added anions on the pitting attack. The adsorption characteristics of these anions on the steel surface play a significant role in the inhibition processes. The PO43--anion has a strong inhibitive effect of chloride pitting corrosion. The effect of different inorganic anions on the pitting corrosion of steel samples I and II (with different composition) was also studied in 0.1 M NaCl solution.