The binodal data of the aqueous two-phase system (ATPS) composed of the polyoxyethylene (10) lauryl ether (POELE10, C(32)H(66)O11) and three sulfate salts (Li2SO4, MgSO4, and ZnSO4) were determined at three temperatures (288.15 K, 298.15 K, and 308.15 K). The binodal data of the investigated systems were correlated with three experience equations, and the satisfactory correlation effect was obtained. For the studied systems, the effect of salt type on the binodal curves was discussed by using phase diagram, the effective excluded volume (EEV), and the Gibbs free energy of hydration of the ions (Delta G(hyd)), and three conclusions were obtained. First, the phase-forming ability of salt is influenced by the valence of cation of salt, namely, when the salt has the same anion, the salt containing the higher valence of cation has stronger phase-forming ability than that with lower charge of cation. Second, the phase-forming ability of salt in the investigated systems was enhanced with the increase in the EEV. Third, under the condition that the anion of salt is at the same level, the more negative Gibbs free energy of cation is, the stronger phase-forming ability of salt is. Meanwhile, the effect of the temperature change on the binodal curves was studied, and it was found that the temperature rising was beneficial to ATPS forming in the investigated systems. The liquid-liquid equilibrium (LLE) composition was determined and correlated by using the Othmer-Tobias and Bancroft equations in the investigated systems, and it was found that the absolute value of the slope of the tie-line rose with the increase in temperature.