The structure of the title compound, [NaRuCl(4)(C(2)H(6)OS)(2)](n), comprises centrosymmetric [RuCl(2)(DMSO)Na(DMSO)Cl(2)Ru] units (DMSO is dimethyl sulfoxide, C(2)H(6)OS), with two Ru atoms, each lying on a crystallographic centre of inversion, connected via Na atoms, DMSO and chloride ligands into a two-dimensional (110) array. Both Ru(III) atoms are octa-hedrally coordinated by four chloride ligands in the equatorial plane and by two DMSO mol-ecules in apical positions within a RuCl(4)S(2) donor set. The Na atom is surrounded by three chloride anions and three O atoms derived from three DMSO mol-ecules, with the resulting Cl(3)O(3) donor set defining an octa-hedron. The crystal structure is further stabilized by inter-atomic inter-actions of the types C⋯Cl [C-Cl = 3.284 (2) Å], C-H⋯Cl [C⋯Cl = 3.903 (3) Å] and C-H⋯O [C⋯O = 3.376 (3) Å].