The complex RuCl2(TRIPHOS)(DMSO). C6H5CH3 is monoclinic, P2(1)/c, with a=21.070(5), b=11.968(3), c=16.892(4) Angstrom, beta=107.7(2)degrees, V=4057.2 Angstrom(3), Z=4. The crystal structure consists of discrete molecules of the complex and solvent held together by normal van der Waals forces. The ruthenium atom is hexacoordinated. Dimethyl sulfoxide binds through the sulfur atom and the TRIPHOS ligand occupies three coordination sites.