Abstract: To investigate the effect of polysaccharides from fermented gloeostereum incaratum on immune function in mice,after feeding with three different dosages(1,5 and 20mg/d) of polysaccharides from supernant of fermented Gloeostereum incaratum,spleen index,serum hemolysin level,phagocytosis rate of macrophages, proliferation rate of T lymphocytes and CD4+/CD8+ratio were detected. Results showed that comparing with negative control of sterile water,all dosage groups had no effect on spleen index,the low dosage group could significantly increase phagocytosis rate of macrophages and proliferation rate of T lymphocytes,medium and high dosage groups could significantly (p<0.05) or extremely significantly (p<0.01) increaseserum hemolysin level , phagocytosis rate of macrophages , proliferation rate of T lymphocytes and CD4+/CD8+ratio . These results indicated that polysaccharides from the supernatant of the fermented G. incarnatum have strong immune enhancement effect in mice.