Low-polydispersity copper nanoparticles (NPs) are prepared through hydrogenolysis of various organometallic copper precursors in an organic medium at moderate temperature. The effects of the precursor composition and the nature of the additional surfactants on the structure and stability of NPs are characterized by TEM and UV-Vis analysis. The improved air stability of copper NPs originating from amidinate copper and stabilized by an alkylamine compound (hexadecylamine) is evidenced and compared with the effect of a long chain carboxylic acid (oleic acid).