Cellulose is the most common organic polymer on the Earth, with an estimated naturally annual production of 1.5 × 1012 tons, and has been considered as an almost inexhaustible source of raw materials.Hence, effective utilization of cellulose not only reduces the consumption of our limited fossil resources but also protects the environment of the Earth.However, processing and derivatization of cellulose are extremely difficult in general, because this natural polymer is neither meltable nor soluble in conventional solvents due to its hydrogen bonded and partially crystalline structure.Therefore, present industrial production of regenerated cellulose and cellulose derivatives are in long time dominated by polluting viscose process and heterogeneous processes.With increasingly tighter govemmental regulations in industries, the need for implementing "green" processes for cellulose processing and exploring alternative routes to functionalize cellulose with simpler reagents and less steps is getting important.