Co/Cu multilayers have been grown by electrodeposition using a potentiostatic technique in a single electrolyte bath based on CoSO4, H3BO3 and CuSO4. X-ray diffraction performed on these multilayers have shown polycrystalline fee structure of both Co and Cu layers with preferential (111) texture. Nuclear magnetic resonance spectrum has been recorded at 4.2 K on [Co(6 nm)/Cu(4 nm)](25) and has shown a resonance line at 216 MHz which confirms the fee structure of Co layers. The analysis of the spectrum showed on one hand that the Co layers are not pure and contain approximately 1.5% of Cu, but on the other hand, the interfaces are of good quality. A cross-sectional on transmission electron micrograph showed a columnar growth morphology. Resistivity measurements performed on this sample presented a giant magnetoresistance (GMR) effect of about 4% at room temperature.