To study the anti-fatigue effect of Pleurotus eryngii,clean Kunming breed mice as the subject of the experiment which were divided into blank controller group,and four Pleurotus eryngii polysaccharides treatment groups(high,medium and low groups)randomly.Every group was intragastric administration with Pleurotus eryngii polysaccharides for 4weeks,then the climbing time,swimming time,hepatic glycogen reserve,muscle glycogen reserve and organ coefficient in each groups of mice were measured.The result shows that different does of Pleurotus eryngii polysaccharides could prolonged the climbing time and swimming time of mice and increased the reserves of hepatic glycogen and muscle glycogen significantly,but there have no significant difference about weight and organ coefficient between each groups.The experimental shows that Pleurotus eryngii polysaccharides have the action of adjuvant anti-fatigue.