The electrochemical behavior of selenite was investigated in the presence of tin(II) in acidic media using cyclic voltammetry. When both selenite and tin(II) were present in solution, two new peaks appeared at -0.31 V and -0.74 V vs. Ag/AgCl/KClsat besides the peaks corresponding to the reduction of Se(IV) to HgSe and Se as well as to the reduction of HgSe and Se peaks. The origin and characteristics of these peaks are discussed. The one at -0.31 V was attributed to the formation of SnSe intermetallic compound, while the other at -0.74 V to the stripping of the SnSe layer. The nature of a peak at -0.57 V appearing just prior to the HgSe stripping peak is also discussed. A comprehensive. picture of the electrochemical behavior of selenite in the presence of Sn(II) is proposed.