Abstract. The mathematical model of electrochemical processes distribution within the three-dimensional fl ow-through electrode for the system Fe(III)/Fe(II)/Fe is described in this paper, considering also the electrochemical reactions of hydrogen and molecular oxygen reduction. Possible dynamic changes in the parameters of electrode, electrolyte and the process are taken into account in the mathematical model, such as electro-conductivity of electrode material, electrolyte fl ow rate, material porosity and specifi c electrode surface, concentrations of electro-active substances and other characteristics within the local volume of electrode. Electrode and process characteristics are treated as time and coordinate functions within the electrode volume. The results of calculations and experimental studies of iron electroreduction are given, the analysis of the numerical modeling is provided.