Cyclic voltammograms of the tin electrode were constructed in NaOH solutions as a function of electrolyte bulk concentration, starting potential and scanning rate and range. The cyclic voltammograms are characterized by five anodic regions and one cathodic peak, which correspond successively to: oxidation of Sn to Sn(OH)//2 or SnO, oxidation of Sn(OH)//2 or SnO to Sn(OH)//4 or SnO//2, reinforcement and/or tightening of SnO//2, solid phase transformation, oxygen evolution on the passive film, reduction of some of the first anodic oxidation products.