The present invention relates to the field of food or health care product, in particular a polysaccharide composition and use thereof. In the present invention, lentinan, pachymaran and tremellan are compounded. The resultant composition can significantly improve the survival rate and quality of life of mice infected by influenza virus, improve the pulmonary inflammatory lesion degree in mice infected by influenza virus, significantly improve levels of specific antibodies in serum of mice infected by influenza virus, significantly decrease the virus content in the lung of mice infected by influenza virus, as well as improve levels of cytokines IL-2 and IL-5 in the lung. In comparison with existing vaccines or single polysaccharides, the polysaccharide composition as provided in the present invention has more significant protective effects on mice infected by influenza virus.