Zinc-nickel binary alloys have been successfully electrodeposited onto steel sheets from baths containing zinc acetate, nickel acetate and acetic acid (pH 4.4-4.6). The potentiodynamic cathodic polarization, cathodic current efficiency, morphology and composition of the deposits were determined for a variety of bath composition, temperature, current density and superimposed ne on dc. The baths are characterized by high cathodic current efficiency for co-deposition. The co-deposition shows an anomalous behaviour with zinc being the preferentially deposited metal. X-ray tests revealed the presence of a single gamma-phase (rich-zinc alloys) with body centered cubic structure.