Chlorodeoxycellulose derivatives have recently assumed importance since the halogen atoms can be changed with other functional groups to afford new derivatives of cellulose. Also, chlorinated cellulose has been employed as an intermediate in the preparation of various functional cellulose derivatives. In this study chlorodeoxycellulose was prepared by reaction of methylcellulose with mathanesulfonylchloride in N,N-dimethylformamide. Subsequently, conversion of the above chlorinated cellulose to unsaturated celluloseen was carried out by potassium tertiary butoxide in dimethyl sulfoxide. An anhydrocellulose as an intermediate for the reactive functional derivatives was made by simple alkali treatment. Preparation condition of allylated methylcellulose by using allylchloride and its thermal behavior were also described.