The solubility of onoxacin in 1,2-dichloromethane, chloroform, carbon tetrachloride, and water was measured by a gravimetrical method from (293.15 to 313.15) K under atmospheric pressure, and the solubility data were correlated against temperature. The solubility is at a minimum in water and a maximum in chloroform. Further, some thermodynamic parameters such as enthalpy, Gibbs energy, and entropy for dissolution have also been evaluated. For 1,2-dichloromethane and chloroform, enthalpy, Gibbs energy, and entropy values are very close and lower than those for carbon tetrachloride and water.