Abstract: It has been shown by cyclic voltammetry that the electrodeposition of Al-Mn alloys was affected significantly by the coneentration of MnCl₂ and temperature. A single amorphous Al-Mn phase would be formed preferentially at higher concentrations of MnCL₂ and lower temperatures. It has also been shown by potential step that the nucleatin rate was small and the growth seemed to be 2-dimensional during the elctrodeposition of amorphous Al-Mn, leading to quality electroplates with few defects.