The passivation and pitting corrosion of tin in sodium gluconate (SG) solutions was studied by using potentiodynamic and cyclic voltammetric techniques. Some samples were examined by X-ray and SEM. The effect of the concentration of gluconate ion, pH, potential scanning rate, successive cyclic voltammetry, switching potential and progressive additions of halide ions on the passivation and pitting corrosion of a tin anode was discussed. The data obtained show that low concentrations of SG have an inhibition effect on the pitting corrosion of tin in neutral media. The pitting corrosion of tin increases with increasing SC concentrations due to the formation of soluble tin-gluconate complex. The critical pitting potential depends on the gluconate ion concentration, pH and scan rate. Two cathodic peaks are observed in the cathodic polarization curve, corresponding to the reduction of the dissolved pitting corrosion products. The critical pitting potential shifts progressively to more negative values with increasing halide ion concentration. In all experiments, the aggressive action of halides decreased in the order Cl- > Br- > I-.