Abstract: objective: Study the effect of functional oligosaccharide from Stachys seiboibi on ability of anti- fatigue in mice.Methods 7- weeks- old male BALB / C mice after one week adaptive feeding were divided into 4 groups: blank control group( saline),low dose group( 125mg·kg- 1·d- 1),medium dose group( 250mg·kg- 1·d- 1),and high dose group( 500mg·kg- 1·d- 1).14 days later,the content of serum urea- nitrogen,hepatic glycogen,muscular glycogen,Hb,the activity of LDH,and the time of weight loading swimming of mice were analyzed. Results:Functional oligosaccharide from Stachys seiboibi could increase the reserve of liver glycogen and muscle glycogen reserves( p < 0.01),improve the content of blood hemoglobin( p < 0.05),reduce the content of serum urea nitrogen after movement( p < 0.01),improve the activity of lactate dehydrogenase after exercise( p < 0.01),and extend swimming time of mice( p < 0.01).Conclusion: The results suggested that functional oligosaccharide from Stachys seiboibi improved the ability of anti- fatigue in mice.