ZnNi coatings were deposited using the electrochemical deposition method. In this study, the effect of potential electrodeposition on deposited properties, morphology, and size of ZnNi alloy nanoparticles was investigated in detail. The as-synthesized products were characterized by ZnNi coating properties is characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and electrochemical impedance spectroscopy (EIS). The result indicated that the electrodeposition processes of ZnNi were governed by a nucleation process controlled by diffusion. XRD results showed that the phase structure of both alloy and composite coatings was single ZnNi phase. Potential increase influences the larger crystal size and the surface of coating was compact and uniform, the Rct increase, and greater the icorr so that the possibility of corrosion is higher.