Two Co(II) coordination polymers, [CoL(npa)]·2H 2 O (1) and [CoL(Hnpa) 2 ] (2) (L = 1,4-bis(5,6-dimethylbenzimidazole-1-yl)benzene, H 2 npa = 5-nitroisophthalic acid), have been synthesized in different solvent systems and characterized by Infrared (IR) spectroscopy, elemental analysis, and powder and single crystal X-ray diffraction. Compound 1 was synthesized under solvothermal conditions with DMF as solvent and had a pair of L ligands adopting a μ 2 -bridging mode and connecting two Co 2+ cations to generate a 26-membered Co 2 L 2 loop. The npa 2− link adjacent Co 2 L 2 loops via a bis(monodentate) bridging mode to create a 1-D channel-like chain structure. Compound 2 was obtained under hydrothermal conditions, and the carboxylate of the monodeprotonated Hnpa − adopt a μ 1 -η 0 : η 1 coordination to connect adjacent Co 2+ cations into a 2-D polymeric layer. The μ 2 -bridging L ligands connect adjacent 2-D [Co(Hnpa)] n polymeric layers into a 3-D NaCl-like framework. The Co 2+ cations and the L ligands in compounds 1 and 2 exhibit different coordination geometries and conformations. Effects of solvents on the construction of Co(II) coordination polymers were investigated. In addition, the electrochemical behavior of carbon paste electrodes containing 1 and 2 and the thermal stabilities of 1 and 2 were investigated.