The solubilities of chloroquine diphosphate and 4,7-dichloroquinoline in water, ethanol, tetrahydrofuran, acetone, and acetonitrile were measured over the temperature range of (298.2 to 333.2) K. The solubilities of both analytes in different solvents increase smoothly with temperature. On the basis of the solubility data, it can be observed that the highest solubilities for chloroquine cliphosphate and 4,7-dichloroqoinoline were obtained in pure water and tetrahydrofuran, respectively. The temperature dependence of the solubility data was correlated by the modified Apelblat model. The calculated solubilities show good agreement with the experimental solubility data in the temperature range studied.