The influence of inorganic salts on sodium dodecyl benzene sulfonate (SDBS)/butanol/octane/water microemulsion system was investigated by changing the type of salts. Increasing cationic charge concentration of various salts in an anionic surfactant microemulsion system promoted changes in the microemulsion phase behavior from lower phase (Winsor Ⅰ) microemulsion through middle phase (Winsor Ⅲ) toward upper phase (Winsor Ⅱ) microemulsion. While for different inorganic salts

optimum salinities were different. Six groups of salt mixture systems were investigated. There was a linear relationship between efficiency parameter of salt mixtures and their composition

in other words

the influence of salt mixtures could be predicted by studying efficiency parameter of single inorganic salts. By using efficiency parameter as the medium

the relationship between optimum salinity of single salts and their mixtures was deduced

and could be used to predict the influence of salt mixtures. The prediction results coincided well with the experimental results.