Biological electrochemical systems, as Microbial electrolysis cells (MEC) or Microbial fuel cells (MFC), use electroactive biofilms in which bacteria have the ability to transfer electrons to an external acceptor. Previous studies have shown difficulties with reproducing the composition of electroactive biofilm microbial communities and also to obtain repeatable performance from a natural inoculum as marine sediments. Electroactivity of bacteria involving their ability to exchange electrons with an external electron acceptor (the electrode), the enrichment method adopted in this study had been chosen to select microorganisms which can reduce iron oxides. Sediments from a salt Plant had been enriched in a medium which contains Fe(III) in which bacteria reduce Fe(III) to form Fe(II). This enriched community had been used to inoculate reactor to form an electroactive biofilm. This process had been reiterated several times to observe the effect of enrichment culture stages on bioelectrochemical process and electroactive biofilm communities. As experimental design, a three-electrode system was used in which the graphite working electrode potential was fixed with a potentiostat (Biologic VSP) according to a reference electrode (SCE). The current produced between the working electrode and an auxiliary electrode was monitored. A voltage of 0.2 V vs SCE was applied to the anode with acetate as carbon source in synthetic seawater, at pH 7 and 37°C. At least, an increase of coulombic efficiency from 15.19±1.91 % to 49.52±3.77% had been obtained. The final biofilm had been collected and microbial diversity is under characterization by 16S and HydA DNA- fingerprinting methods.