Corrosion behavior of Zn-Mn alloys was studied through polarization resistance test and electrochemical impedance spectroscopy in 3% NaCl solution. Compared to pure Zn, Zn-10.1%Zn coating exhibits high corrosion resistance. The evolution of R_p with the Mn content seems to be ascribed to two mechanisms of Zn-Mn deposits dissolution, leading to two surface states. The differentiation is linked to the absence or the presence of the corrosion products layer on Zn-Mn deposit surface. The Nyquist impedance plots shape depends on the Mn content. This shape difference reveals a difference in phenomena possible to occur at the deposit/corrosive environment interface