To exploit the valuable features of brine resources with high concentrations of borate ions, the solubility data and corresponding physicochemical properties (refractive index, density, viscosity, and pH) for the reciprocal quaternary system (Na+, Ca2+//Cl-, borate-H2O) at 288.15 K were determined experimentally using the method of isothermal dissolution equilibrium. The dry-salt and water-phase diagrams and the diagrams of physicochemical properties (refractive index, density, viscosity, and pH) against J(B4O72-) in the solution were established. In the dry-salt phase diagram of the quaternary system at 288.15 K, two invariant points, five univariant curves, and four crystallization regions corresponding to gowerite (CaB6O10 center dot 5H(2)O), borax (Na2B4O7 center dot 10H(2)O), antarcticite (CaCl2 center dot 6H(2)O), and sodium chloride (NaCl) were found. The area of crystallization region of CaB6O10 center dot 5H(2)O is larger than that of other coexisting salts, which indicates that the solubility of gowerite in this system is the lowest and that it is more easily separated by crystallization; the areas of crystallization regions of Na2B4O7 center dot 10H(2)O, NaCl, and CaCl2 center dot 6H(2)O are decreased in turn. In this system, there are no double salts or solid solutions experimentally found. The water-phase diagram of the system indicates regular variation of J(H2O) on J(B4O72-), and the physicochemical properties of the quaternary system varied regularly with increasing Janecke index values of J(B4O72-).