In this work, experimental solubility data of para-tert-butylbenzoic binary solvents of acetic acid + water (293.15 to 333.15) K, methanol + water (293.15 to 328.15) K, and acetic acid + para-tert-butyltoluene (293.15 to 323.15) K were studied over acetic acid/methanol mass fraction, w(2) (on solute free basis) of 0.1 to 0.6 at temperatures of 5 K intervals. The solubility measurements showed that acetic acid + para-tert-butyltoluene recorded higher solubility than acetic acid/methanol + water for the same mass fraction of acetic acid at each temperature. Moreover, solubility increases with increase in temperature for the studied binary systems and the acetic acid + para-tert-butyltoluene system presents a maximum solubility effect at mass fraction of 0:2 (0.38 mole fraction) of acetic acid. Several thermodynamic models such as Buchowski-Ksiazczak equation, the Van't Hoff equation, the modified Apelblat equation and NRTL model were fitted: to the experimental data and the optimum, values of the regressed parameters were presented: The results indicate that the Van't Hoff and Buchowski-Ksiazczak equation represent the experimental findings better compared to other models based on the average absolute percentage deviation (delta(AAPD)).