Ketoconazole is an important drug with low water solubility. Its low aqueous solubility could be increased using various methods such as by the addition of a pharmaceutical cosolvent. The solubility of ketoconazole in ethanol + water mixtures at 293.2, 298.2, 303.2, and 308.2K were determined, and the results showed that the addition of ethanol increased the solubility and the maximum value was obtained at 80% of ethanol. The generated data were mathematically represented using the Jouyban-Acree model within an acceptable accuracy.