A dinuclear copper(II) complex of [Cu2(aceace)4(dipyph)] [aceace = acetylacetone, dipyph = 1,4-di(4-pyridylethene-2-yl-)benzene] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. It crystallizes in the monoclinic system, space group P21/c, with lattice parameters a = 7.9584(16) Å, b = 18.594(4) Å, c = 15.063(4) Å, β = 120.97 (2) o and Mr = 807.85 (C40H44Cu2N2O8), Z = 2. Each of the Cu 2+ ion adopts a square pyramid geometry and coordinates with four oxygen atoms from two aceace ligands and one nitrogen atom from dipyph bidentate ligand. Magnetic measurement shows that the Weiss constant and Curie constant for the title compound are -0.22 K and 0.1154 emu·K/mol, respectively. Thermal stability data indicate that the title complex undergoes two steps decomposition and the residue is Cu2O4. In the potential range of -1.5 ~ 0.8 V, the title complex represents an irreversible electrochemical process.