In this thesis, the block copolymer containing polysaccharides and synthetic polymer was synthesized. In order to introduce the polysaccharide into block copolymer structure, two methods were mainly used, which are polymerization of synthetic polymer with using polysaccharide as macroinitiator, or end-to-end coupling reaction between end of polysaccharide and end of synthetic polymer. Both of methods fundamentally need the end-functionalization of polysaccharide. The reducing end of dextran was functionalized to alkyne group and amine group, so that the optimum condition for end-functionalization could be found. Between the two synthetic routes of polysaccharide-containing block copolymer, the coupling reaction was selected, and especially click chemistry was used for synthesis of block copolymer. Before the click reaction between dextran and polystyrene was conducted, for dissolving the two materials in co-solvent, the protection of hydroxyl groups of dextran was performed by silylation. The structure of synthesized dextran-block-polystyrene copolymer was analyzed by GPC and $^1$H NMR.