In this study, a simple route has been presented for the preparation of size-tunable metal (Pd, Ag) nanoparticles (NPs) based on polyacrylonitrile (PAN) nanofibers through electrospinning and microwave irradiation. PAN nanofibers containing metal salts (PdCl2 and AgNO3) were prepared through electrospinning and then the salts were reduced to metal NPs under microwave irradiation. The diameters of the metal NPs can be controlled by varying the molar ratio of PdCl2 to PAN and the concentration of NaOH. The structures and distribution of the metal nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). (C) 2007 Elsevier B.V. All rights reserved.