In the present work, 1D-copper(II) coordination polymer, {[Cu(mu-l-Arg)(2)(H2O)]SO4}(n)(1); (l-Arg:l-Arginine), was synthesized and identified by elemental analysis, FT-IR spectroscopy, molar conductivity, thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and single-crystal X-ray diffraction. The compound1was also prepared by a sonochemical process in the form of nanoparticles. The particle size and morphology of the synthesized nanoparticles were investigated by powder X-ray diffraction (PXRD) and field emission scanning electron microscopy (FE-SEM). In the crystal structure of1, the copper atoms are coordinated in a distorted octahedral geometry. In this geometry, thecis-equatorial plane (N2O2) is constructed by two NO-donorl-Arg ligands. The remaining coordination sites in the apical positions are occupied by an oxygen atom of the neighboringl-Arg and the oxygen atom of a water molecule. In1, infinite one-dimensional (1D) networks are constructed through carboxylate bridges. Finally, CuO nanoparticles were produced by thermal decomposition of the sonochemically prepared nanoparticles of1, and characterized by FT-IR, XRD, FE-SEM and EDS.