In the present work some physical properties of binary zinc chloride-dimethylsulfone (ZnCl 2 - DMSO 2 ) melts were investigated; the phase diagram was determined by Differential Scanning Calorimeter (DSC) and Thermogravimetric Analyzer (TGA) analyses; the electric conductivity was measured using a direct-current computerized method. The conductivities of the melts increased with increasing temperature and DMSO 2 content. There was a maximum of the conductivity at 40 mol% ZnCl 2 ; the conductivity was 0.00423 S/cm at 110 ◦ C. The density of all the melts decreased with increasing temperature and DMSO 2 contents. The equivalent conductivities were given by Λ =κM mix /ρ, where M mix is the mean equivalent weight. These equivalent conductivities were fitted by the Arrhenius equation, where the activation energies were 25.2, 34.6, 44.5, 53.7 kJ/mol for 40, 50, 60, 70 mol% ZnCl 2 , respectively.