Abstract: OBJECTIVE To study the antibacterial effect and antioxidant activity of Grifola frondosa polysaccharide. METHODS UV spectrophotometry was used to determine the content of polysaccharide, D-anhydroglucose was used as a standard. The antibacterial effect produced by Kirby-Baue method with the bacteria of Staphylococcus aureus, Escherichia coli and Bacillus subtilis. Took the scavenging capacity as index to estimate the endogenous antioxidative activity of DPPH and T-AOC. RESULTS The total polysaccharides in Grifola frondosa extract was 53.82%. Grifola frondosa polysaccharide had a good antibacterial effect on Staphylococcus aureus, Escherichia coli and Bacillus subtilis, the diameter of antibacterial were 13, 11, 10 mm. With the concentration between 0.05~10 mg·mL^-1, Grifola frondosa polysaccharide had a good scavenging activity by DPPH, when the concentration above 0.5 mg·mL^-1, showed the total antioxidant activity. CONCLUSION The polysaccharides in Grifola frondosa has certain antibacterial effect and antioxidant activity.