At electrodeposition of galvanic coatings reduction of metal ions is the main cathodic reaction. However often one, two or more electrochemical and chemical reactions take place on the electrode. It occurs because of there are some components and surface of metal in the electrolyte, which undergo electrochemical transformations at given potential. In the process of metals deposition on more electrochemical active basis accompanied reaction of metal ionization takes place. In some cases basis is passivated, which has significant influence on adhesion of coating. Actually, this is a complex of minimum 2 co-reactions: cathode reduction of ionsof electropositive metal M2 anode acidation of basis metal M1,Properties of plating, including optical property of surface are determined by composition of deposit, presence of inclusions, texture of surface. Most often hydrogated oxides or sulfide of metals, which are formed as a result of co-reactions in near-electrode (cathode) layer, are included to the deposit. Investigation of co-reactions influence on process of galvanic coating formation helps to find out how to purposefully manage properties of coating and process of its production. This will facilitate to develop new electrolytes for plating of coating Objects of study: • process of contact exchange, determined by co-reactions of copper ions (II) reduction and ionization of stale of different kinds in acid, neutral and basic electrolytes. • during the deposition of metals on aluminum there is a complex of three coreactions: anodic dissolution of aluminum, cathode reduction of metal ions and proton donors. The production of hydrogen mainly takes place on the surface of metals, where overstrain of the hydrogen production is lower. • process of mechanical plating of zinc and subpotential deposition of zinc on iron and copper electrodes • copper decorative wooden coatings electrodepositing • black cobalt solar selective coating electrodepositing process We came to the conclusion, that during plating on more electrochemical active basis metals accompanied reaction of metal ionization or passivation takes place. It influences on adhesion of coating. Property of plating, including optical property of surface is determined by inclusion of hydrogated oxides or sulfide of metals, which are formed as a result of co-reactions in nearelectrode (cathode) layer.