Complex [H(dmso)]₂[Os^IVCl₆] ⋅ 2H₂O (1) was synthesized by refluxing of [H(dmso)₂]₂[OsCl₆] in concentrated HCl and characterized by the IR and UV/Vis spectroscopy and X-ray powder and single-crystal diffraction studies. In this complex, rare highly electrophilic [Me₂S=O⋅⋅⋅H]⁺ cation is stabilized by multiple chalcogen bonds including bifurcated S⋅⋅⋅(Cl)₃ and S⋅⋅⋅Cl non-covalent interactions. DFT calculations and topological analysis of the electron density distribution within the formalism of Bader's theory (QTAIM method) support the presence of intermolecular non-covalent interactions S⋅⋅⋅Cl and O⋅⋅⋅Cl in the solid state.