Physicochemical properties of ZnCl2-NaCl-KCl eutectic melt were studied at 200-300 degrees C for the first time. Firstly, it wits reconfirmed that the eutectic composition is ZnCl2:NaCl:KCl =0.6:0.2:0.2 in mole fraction, and that the eutectic temperature is 203 degrees C. Then, the density, viscosity, and ionic conductivity of the ZnCl2-NaCl-KCl eutectic melt were measured at 200-300 degrees C. At 250 degrees C, the density was 2.43 g cm(-3), the viscosity was 42.0 cP and the ionic conductivity was 8.53 S m(-1). The temperature dependencies of density and ionic conductivity were well fitted by the VTF equations with the same ideal glass transition temperature of 283 K (10 degrees C). It was found that the melt obeys the fractional Walden's rule which is explained by the decoupling effect. The electrochemical window of the melt was determined to be 1.7 V at 250 degrees C with the cathode limit being zinc metal deposition and the anode limit being chlorine gas evolution. (C) 2009 Elsevier Ltd. All rights reserved.