<p>The influence of Mn²⁺ concentration and the deposition times on the electrodeposition of Zn-Fe-Mn alloy from acidic sulfate baths were investigated. They have been achieved on low carbon steel at 25&#xa0;°C using cyclic voltammetry (CV), chronopotentiometry to deposit the coatings galvanostatically and anodic linear sweep voltammetry (ALSV). The structure and morphology of deposits were characterized by x-ray diffraction (XRD), energy-dispersive x-ray (EDX) and scanning electron microscopy (SEM). The obtained results revealed that Zn content decreases gradually; however, Fe content increases, and a new intermetallic phase of Mn_0.27Zn_0.73 was formed at the highest concentration of Mn²⁺ and at the highest deposition time. The SEM analysis showed that the Zn-Fe-Mn alloys at high Mn²⁺ concentration and at high deposition time exhibited more homogenous and compact surfaces. The corrosion performance of the formed coatings on low carbon steel has been examined in 3.5% NaCl solution at 25&#xa0;°C using the potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) techniques. The results prove that the increase in corrosion resistance and the inhibition efficiency is attributed to the formation of Mn_0.27Zn_0.73 phase at high concentration of Mn²⁺ and formation of both Fe₃Zn₁₀ and Mn_0.27Zn_0.73 phases at high deposition time.</p>