We investigated the chemical, physical, and tribological properties of nanolubricants consisting of epoxidized sunflower oil with Cu nanoparticles as additive. These latter are produced by magnetron sputtering at distinct current levels in the deposition, to improve the development of nanolubricants by enhancing the nanoparticles dispersion. The nanolubricants are here characterized by Fourier transform infrared spectroscopy, zeta potential, ultraviolet–visible absorbance spectroscopy, small-angle X-ray scattering, and scanning electron microscopy. After all, the tribological properties of the bionanolubricants are investigated using a high-frequency reciprocating rig equipment, scanning electron microscopy, and energy dispersive spectroscopy. Our results disclose the nanolubricants produced using the magnetron sputtering technique have excellent nanoparticle dispersion, as well as good tribological performance.