The equilibrium phase diagrams of NaCl-ZnCl2-H2O system at 260.35 and 250.15 K were studied by method of isothermal solution saturation, wet residues, and thermogravimetric analysis. Water content in precipitate at these temperatures for hydrate 2NaCl center dot ZnCl2 center dot nH(2)O was determined, n = 3. Densities of ternary NaCl-ZnCl2-H2O solutions were measured at 288.15-321.35 K and compared with values predicting by the Laliberte model. It was shown that the model provides mainly underestimated density values.