Ag core-Cu shell nanoparticles, denoted as Ag@Cu, were synthesized in high yield (100%) using a one-pot polyol method under bubbling Ar gas. AgNO3 and Cu(OAc)(2)center dot H2O were used as reagents. The formation of Ag@Cu particles and their crystal structures were examined using energy dispersed X-ray spectroscopic (EDS) measurements and selected area electron diffraction (SAED) patterns. The growth mechanism of Ag@Cu is discussed.