The electrodeposition of copper-rhenium alloys from Cu(II) and Re(IV) solutions was studied in an aqueous H,SO, matrix. Different substrates have been used (glassy carbon, titanium and gold), and the effect of them on the electrochemical behavior of the studied ions is shown. Cyclic voltammetry was used in conjunction with oscillating quartz crystal nanogravimetry to delineate features in the voltammograms accompanied by mass loss or gain at the electrode surface, from those attributable to the solution phase. The obtained Cu-Re films were subjected to scanning electron microscopy (SEM). energy dispersive X-ray analysis (EDX) and X-ray diffraction analysis (XRD). The rhenium content increases as the potential was made more cathodic, reaching a maximum value of 10% atomic composition. The films were amorphous with a cauliflower structure.