The title compound, cis,fac-dichloridotetra-kis(dimethyl sulfoxide)-κ(3)S,κO-ruthenium(II), [RuCl(2)(C(2)H(6)OS)(4)], was obtained from newly synthesized ruthenium complexes of 3-amino-2-chloro-pyridine. The Ru atom has a distorted octa-hedral coordination with two cis-oriented chloride ligands and four dimethyl sulfoxide ligands. Three of the sulfoxide ligands are S-bonded in a fac configuration, while the fourth is O-bonded. The title compound represents a new, and fourth, polymorph of the complex. Two other monoclinic forms and an ortho-rhom-bic modification have been reported previously.