The intercalation of kaolinite is the key to the preparation of polymer layered silicate nanocomposites. In this paper, the research advances in intercalation mechanism of kaolinite are summarized, and the intercalation mechanism is discussed in detail, which includes several aspects of the reaction and orientation of the molecule in the lamella, the role of the water in the intercalating process, the absorption and intercalation, and the de-intercalation. In addition, the potential application of kaolinite/organic intercalated composites is described. On such a basis, the key points in this research field are indicated.