Bismuth - oxide layers on a titanium are created by a plasma electrolytic oxidation (PEO) method from the electrolytes containing Bi (III) complex salts. Electrochemical characteristics – exchange currents, transport coefficients α and β, a and b coefficients in Tafel's equation are defined. For the received systems emergence of an analytical signal at complexometric titration of salts of Fe (III) is established. The structural features of  surface electrodes have been investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectros-copy (XPS) techniques. Correlation between morphology, structure of a surface and electrochemical properties of exemplars is found.