In the title compound, [Na(C(6)H(3)Cl(2)O(3)S)(H(2)O)](n), the Na(I) ion is penta-coordinated by three dichloro-benzene-sulfonate anions and two water mol-ecules, forming a distorted trigonal-bipyramidal geometry. The Na(I) ions are bridged by the sulfonate groups and the water mol-ecules, leading to a polymeric layer structure parallel to the bc plane in which O-H⋯O hydrogen bonds are observed.