AbstractA new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized. It crystallizes in the triclinic system, space group P-1 with a = 5.645(4), b = 7.905(5), c = 13.043(8) Å, a= 89.391(7), β = 80.637(7), γ = 82.845(7)°, V = 569.8(6) Å3, Z = 2, C7H11NaO8S, Mr= 278.21, Dc= 1.622Kg/m3, F(000) = 288, R = 0.0260 and wR = 0.0697. The title compound consists of one-dimensional double chains. 4-Carboxy-benzenesulfonic acid acts as a bridging bidentate ligand to link two sodium(I) ions to form a binuclear structure. Remarkably, the sodium(I) ion behaves as a metal bridge so that the binuclear structure units are connected to construct a one-dimensional double chain polymer. Furthermore, a 3-D framework is assembled through intermolecular hydrogen bonds. Thermogravimetric analysis shows that this compound begins losing the free solvent molecules at 106 ℃ and decompounding completely at 580 ℃.