The densities and viscosities of binary and tertiary Solutions of the aqueous two-phase systems created by the Polyethylene glycol 6000 + triammonium citrate + water system were measured at different temperatures [(25, 30, 35, 40, and 45) degrees C] and correlated with empirical equations. The density data were compared With those available in the literature. The density data show a linear variation with the mass fraction Of the polymer for all temperatures The density and viscosity of the top and bottom phases were also measured and reported.