This paper presents a rapid method for preparation of copper metal nanoparticles by reducing CuSO(4)(.)5H(2)O with (NaH2PO2H2O)-H-. in ethylene glycol under microwave irradiation. The influences of the reaction parameters, such as the concentrations of reducing agent and protective polymer time of microwave irradiation, on the size and agglomeration of copper nanoparticles were investigated by X-ray powder diffraction and transmission electron microscope. Well-dispersed copper nanoparticles with diameter of about 10 nm were obtained. The use of microwave irradiation accelerated the reaction rate and benefited the dispersion and the particle size distribution of the nanoparticles. (C) 2004 Elsevier B.V. All rights reserved.