The growth mechanism of Cu/Ni multilayers, electrodeposited from a single bath on a polycrystalline copper substrate, has been studied both electrochemically and through transmission electron microscopy. It is shown that Cu/Ni multilayers grow epitaxially sequentially in the preferential crystallographic directions [110] and [111], when the modulation distance is less than approximately 10 nm. Above this value, the epitaxial growth is progressively replaced by a growth mechanism which is based on nucleation followed by grain growth. This work also demostrates that electrodeposition has a capacity to produce Cu/Ni multilayers with modulation distances below 5 nm.