Abstract: Xanthogenate was synthesized through reaction of β-cyclodextrin （β-CyD） with carbon disulfide in alkaline solution. It was then reacted with methyl 2-bromobutyrate to produce β-cyclodextrin xanthate as the chain transfer reagent in reversible addition-fragmentation chain transfer polymerization (RAFT). Three graft copolymers β-CyD-PDMA with different chain length were prepared. The structures of β-cyclodextrin xanthate and copolymers were characterized with NMR analysis. The reaction of viscosities, surface tension relation with chain length were studied. The molecule asymmetry was studied by using circular dichroism. The self-assembly behavior of β-CyD-PDMA was studied using highresolution transmission electron microscopy and dynamic light scattering. The results indicate that three 6-hydroxyl groups of β-cyclodextrin are functionalized, and the copolymer is an asymmetrical crown-like molecule; all the copolymers have narrow molecular weight distribution that is characteristic of controlled polymerization; all copolymers can form micelle, but copolymer with long PDMA chain exist two assemble manners: forming micelle with a diameter of 280 nm at low concentration, while forming a new aggregation with a diameter of 6 nm at high concentration.