Two new copper(II) complexes (I, II) with benzimidazole ligands have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Compound I is triclinic, P1, a = 11.4205(6), b = 13.0956(7), c = 18.2305(9) angstrom, alpha = 85.960(1)degrees, beta = 80.388(0)degrees, gamma = 77.517(1)degrees, V = 2623.0(2) angstrom(3), Z = 2; compound II is monoclinic, C2/c, a = 24.2684(11), b = 17.5247(8), c = 19.3149(15) angstrom, beta = 122.710(1)degrees, V = 6911.9(7) angstrom(3), Z = 4. In both compounds, Cu(II) atoms are coordinated by four benzimidazole nitrogen atoms in a slightly distorted tetrahedral fashion.