Objective:To research the biological activities of polysaccharide from Polygonatum Sibiricum Redoute.Methods:1.Adding PSP to mouse's feed stuff and determining the inhibition of serum lipids by PSP.2.Feeding mouse with PSP to determine PSP's function of anti-aging.3.Feeding mouse with PSP to determine the immune activities.Results:1.PSP has obvious effect in preventing from and treatment of mouse hypercholesterolemia.2.PSP can increase the activities of SOD and GSH-Px in aged mouse blood and decrease the content of LF and MDA in aged mouse heart,liver() and brain.3.PSP has a strong ability to enhance mouse Phagocyte's Phagocytic percentage and Phagocytic index,to increase the content of haemolysin in mouse and the response of the DTH(delayed-type hypersensitivity) in normal mouse and to recover response to DTH in cyclophosphamide(Cy)intoxicated.Conclusion:PSP can reduce the serum lipids,deter aging and enhance the immune reaction in mouse.