This paper reports on the biosynthesis of copper nanoparticles (NPs) using extract of the Euphorbia esula L leaves as reductant and stabilizer without any surfactant. The catalytic efficiency of the prepared Cu NPs for the reduction of 4-nitrophenol and ligand-free Ullmann-coupling reaction is discussed. The Cu NPs were characterized with UV-vis, XRD and TEM methods. This method has the advantages of high yields, simple methodology, and elimination of ligand and easy work up.