Two kinds of microemulsion systems for quaternary ammonium salts surfactan, octadecyl trimethyl ammonium chloride (OTAC) and hexadecyl trimethyl ammonium bromide (CTAB) ,were studied on their solubilization properties for single organic compound and organic mixtures (n-octaneand binary mixtures of n-dodecane/n-hexane, n-dodecane/ n-heptane and n-dodecane/n-octane). The optimal alcohol dosage (A*) and the optimum solubilization parameter (SP*) of Winsor III microemulsions were studied. The results suggested that the two surfactant microemulsion systems showed similar patterns. With the increase of salinity, SP* increased monotonically and A*decreased monotonically. With the increase of surfactant concentration, A* increased, while, SP *increased first and then decreased. For the binary organic mixtures, the relationship between A* and EACN or SP* and EACN is the same no matter what is the components in the organic mixtures. The fitted equations for the binary organic mixtures were used in the prediction for quaternary organic mixtures. The predicted A* and SP* data coincided with the experimental values satisfactorily, which means that the obtained functional relationship can be used to predict A* and SP*in the similar range of EACN for different organic mixtures.