The solubility of two erlotinib hydrochloride polymorphs (form A and form B) in methanol, ethanol, isopropanol). acetone, methyl ethyl ketone, and methyl isobutyl ketone from 273.15 to 323.15 K were determined by means of high-performance liquid chromatography (HPLC). The modified Apelblat equation and the Buchowski-Ksiazczak lambda h equation were used to correlate the experimental solubility data. The results showed that the solubility of both forms generally increased with the temperature and at a given temperature decreased with the increase of the carbon number of alcohols; furthermore, methyl isobutyl ketone showed the largest solubility in the studied ketones. Meanwhile form A had a higher solubility than form B which demonstrated that form A was the metastable form. Furthermore, both models mentioned above gave satisfactory correlation results, in which the modified Apelblat equation worked better than the Buchowski Ksiazczak lambda h equation.