Abstract: Caseins, the main components of milk protein, represent about 80% of the total protein in the milk. Owing to the importance of casein and casein micelles for the functional behavior of dairy products, and widely application of caseins, the study of casein is always drawing more attention. Especially, the exact structure of casein micelles is still under debate. Many scholars have proposed various theoretic models for casein micelle structure. This paper reviewed kinds means of casein micelles structure, dissociation and aggregation in order to provide a reference for studying casein in the future.