A novel coordination polymer, {[Co(CBA)(BIMB)(0.5)]center dot H2O}(n) (1, H(2)CBA = 4,4'-(propane-2,2-diyl)dibenzoic acid, and BIMB = 4,4'-bis(1-imidazolyl)biphenyl), has been hydrothermally prepared and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P2/c with a = 14.909(3), b = 7.1963(15), c = 24.592(5) angstrom, beta = 104.312(2)degrees, V = 2556.5(9) angstrom(3), C26H23N2O5Co, M-r = 502.39, D-c = 1.305 g/cm(3), F(000) = 1040, mu = 0.708 mm(-1) and Z = 4. The final R = 0.0580 and wR = 0.1605 for 3228 observed reflections (I>2 sigma(1)). Single-crystal structure analysis shows that complex 1 exhibits a three-dimensional 2-fold interpenetrating pillared helical-layer open framework of alpha-Po topology based upon binuclear paddlewheel units. Moreover, its magnetic properties have also been investigated.