A new nickel(Ⅱ) coordination complex [Ni(2,2'-bipy)2(ClC6H4COO)(H2O)](ClO4) was synthesized by self-assembly reaction of m-chlorobenzoic acid, 2,2'-bipy and Ni(ClQ4h·6H2O. The crystal of the title compound belongs to monoclinic system, space group P2(1/n) with a = 0.77764(14), b = 2.6572(5), c = 1.3637(2) nm, β = 96.456(3)°, V= 2.8000(9) nm^3, D,, = 1.528 g/cm^3, Z = 4, Mr = 644.10, μ(MoKα) = 0.937 mm^-1, F(000) =1320, R = 0.0549 and wR = 0.1164. Structure analysis shows that the nickel(Ⅱ) ion is coordinate...