A new general method of preparation of dinuclear thiolate-bridged ruthenium(I) complexes is reported. Compounds of the type RU(2)(CO)(4)(mu(2)-S-2(CH2)(n))(PPh(3))(2) (n = 2 and 3) (I) and Ru-2(CO)(4)(mu-SR()2)(PPh(3))(2) (II) were formed by reacting RU(2)(CO)(4)(mu-O2CH)(2)(PPh(3))(2) with an excess of dithiol or thiol in good yields, Different structural isomers of Ru-2(CO)(4)(mu-SR)(2)(PPh(3))(2) (II) thiolate complexes were found which were separated by chromatography on a silica column. The X-ray structure of the compound RU(2)(CO)(4)(mu-S-2(CH2)(3))(PPh(3))(2) shows that the dithiolate ligand bridges symmetrically two Ru(CO)(2)(PPh(3))(2) fragments. The short Ru-Ru distance agrees with a metal-metal bond and the PPh(3) ligands are nearly trans to the Ru-Ru bond.