catena-Poly[(diaqua-cadmium)-μ-4,4'-[sulfonyl-bis-(1,4-phenyl-ene-oxy)]-di-acet-ato-κO,O':O'',O'''].

In the title coordination polymer, [Cd(C(16)H(12)O(8)S)(H(2)O)(2)](n), the Cd(II) ion is situated on a crystallographic twofold rotation axis, being coordinated by four O atoms from two bidentate 4,4'-[sulfonyl-bis-(1,4-phenyl-ene-oxy)]diacetate (L) ligands and two water mol-ecules in a highly distorted CdO(6) octa-hedral geometry. Each complete ligand L, which is also generated by twofold symmetry with the S atom lying on the rotation axis, bridges two Cd(II) atoms to form a polymeric zigzag chain propagating in the [10-1] direction. O-H⋯O hydrogen bonds between the coordinated water mol-ecules and carboxyl-ate O atoms are involved in the packing.