Hypertension is a common disease endangering human health, modern medicine has revealed that chloride ion is the culprit causing hypertension. Chitosan oligosaccharide by virtue of the unique positively charged characteristics, and was negatively charged chloride ion binding, excreted, can activate vascular cells, improve microcirculation, decrease peripheral vascular resistance, reduce lipid deposition in the vascular wall, so as to realize the role of regulation of blood pressure. Long-term use, can remove the blood acidic waste, soften blood vessels, enhance the elasticity, fundamentally adjustment, alleviate high blood pressure.