Objective: To study the hypoxia tolerance and anti-fatigue of “Mai Wei Shen” in mice and to provide the basis for further development and application  Methods: ① Hypoxia tolerance experiment:Two hundred and forty SPF male mice were randomly divided into four groups:normal saline group, “Sheng Mai Yin” groups (high, medium and low dose), with 60 mice in each group; each group was treated with the corresponding measurements. The survival times in hypoxia tolerance test, after sodium nitrite poisoning and in acute cerebral hypoxia, the content of cyanide high-speed rail hemoglobin, and the contents of SOD, GPX and MDA were detected after 30 days. ② Anti-fatigue experiment:Forty-eight SPF male mice were randomly divided into four groups:normal saline group and “Sheng Mai Yin” groups (high, medium and low dose), with 12 mice in each group; each group was treated with the corresponding measurements. The contents of BLA, BUN, hepatic glycogen, muscle glycogen and exhaustive swimming time of mice after exercise were determined by weight loading swimming experiment  Results: ① Hypoxia tolerance experiment:Compared with the normal saline group, “Mai Wei Shen” could markedly prolong the survival time in hypoxia tolerance test, survival time after sodium nitrite poisoning and the survival time in acute cerebral hypoxia, and reduce the content of cyanide high-speed rail hemoglobin and contents of MDA, increase the activity of SOD and GPX markedly (P<0.05). ② anti-fatigue experiment:Compared with the normal saline group, “Mai Wei Shen” could prolong the exhaustive swimming time, increase the contents of hepatic glycogen and muscle glycogen, and reduce the concentration of serum BLA and BUN (P<0.05)  Conclusion: “Mai Wei Shen” has the certain effect on increase of hypoxia tolerance and relieving fatigue.