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In recent decades, porphyrin systems, which are composed of catalytic MeN4-center, have received much attention due to their unique chemical and physicochemical properties. Indeed, these materials operate in different devices for nonlinear optical and optical limiting devices, photoluminescent biosensors, electrochemical or spectrometric sensors, molecular electronic junctions and electrocatalytic systems. In recent years, the first representatives of the new family of electroactive materials have been obtained.These are polymers of porphine monomer units linked either by meso–meso single bonds (polyporphines of type I, pMP-I) or by three (meso–meso and two beta–beta) bonds (polyporphines of type II, pMP-II), with various coordinated ions M: Mg+2, Н+, Zn+2 и Co+2. Numerous studies have reported that Co(II) porphyrins are useable as sensing molecules for the detection of many different substances such as sulphites or volatile organic compounds. These cobalt complexes have also been exploited as electrocatalysts for fuel or solar cells. So, to expand the new class of electroactive materials that are promising for various potential applications, it is of interest to introduce transition metals in the polymer structure of pMP that would impart electrocatalytic properties to the polyporphine matrix by insertion new ion Fe+2. *** This paper presents an easy, efficient and reproducible way to obtain Fe (II) polyporphine films. A fast three step process based on electrosynthesis of magnesium polyporphine of type I followed by a demetallation in acid and then Fe insertion inside the porphine units allowed us to obtain an interesting material with a high density of active Fe(II) centers. Kinetics studies were conducted to determine the best conditions for the demetallation and remetallation steps. Oxidative transformation of this polyporphine pFeP-I was performed, which led to the formation of additional bonds between the neighboring porphine units in the polymer film (transition of polymer of type I into polymer of type II, pFeP-II). The behavior of the polymer films of Fe (II) polyporphine of types I and II in oxygen electroreduction was studied. The films showed catalytic activity in this process. Moreover, IRATR and UV-visible measurements attested that the initial molecular structure of the porphine units was kept during the three step process. Qualitative composition of polyporphine films has been confirmed via XPS and EDX methods. In situ specific conductivity of these polyporphine polymers of type (I) has been determined as a function of the imposed potential, i.e. of the oxidation degree.