Ni-Mo alloys have been studied as a prospected cathode for its higher hydrogen evolution reaction properties than other binary compounds. The eletrodeposition parameters and its effects have been investigated in forming Ni-Mo alloys in the present study by measuring the structure and properties of deposits. The forming mechanism of Ni-Mo amorphous deposit is discussed from point of the elements component of view. The X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) microstructures show that the molybdenum content in the deposit is increased with the molybdate concentration increase, and the deposit structure can be parted several stages- nanocrystal, nanocrystal/amorphous, amorphous, crystalline, or the mixed configuration due to the variation of Mo atom content. The forming mechanism of the deposit of Ni-Mo alloys is attributable to the repulsive aggradations as of the molybdenum chemical properties and electronic shell structure. When the atom rate of Ni/Mo is higher than 0.35, the deposit is the face center cubic (fcc) configuration, while lower than 0.35, the deposit is the monoclinic hexagon crystalloid configuration or body center cubic (bcc) dimensional structure.