The solubility relationships of the ternary systems ZnCl2-MgCl2-H2O and ZnCl2-PbCl2-H2O at 323 K were studied by isothermal dissolution equilibrium method in this work. For the ternary system ZnCl2-MgCl2-H2O, the phase diagram contains two invariant points, three univariant curves, and three crystalline regions corresponding to MgCl2 center dot 6H(2)O, MgZnCl4 center dot 6H(2)O, and ZnCl2 at 323 K, while the double salt MgZnCl4 center dot 5H(2)O was produced in the same system at 373 K. The ternary system ZnCl2-PbCl2-H2O is a simple cosaturated system with only one invariant point that is saturated with PbCl2 and ZnCl2, two univariate curves and two crystallization zones corresponding to PbCl2 and ZnCl2, and the crystallization zone of PbCl2 is much larger than that of ZnCl2.