Carboxymethyl chitosan, a water-soluble chitosan derivative, has a lot of characteristics such as strong antibacterial property and refreshment, and is a polyamphoteric electrolyte. It is widely applied in cosmetics, refreshment and medicine industry, and it is also one of chitosan derivatives which have been researched often in recent years. Carboxymethyl chitosan, a kind of chemical composite which appeared in recent years, it is going to play a more important role in human’s future daily life due to its pharmacological actions such as stable property, antibiosis, anti-infection, lowering lipid and preventing & curing arteriosclerosis.