：The anti-fatigue, reduced cholesterol function, acute toxicity and the mutagenicity of extraction of characteristic components in Yunnan pu-erh tea were studied using mouse as experimental animals. It had significant function of anti-fatigue and reduced cholesterol for mouse, its effects was better than that of water extracts of pu-erh tea. The oral acute toxicity in mouse,Ames test,micronucleus test in bone narrow and chromosome abnormality test of characteristic components extraction in Yunnan pu-erh tea were also carried out．The oral LD₅₀ value of this extraction in mouse was more than 10.0βg/kg．The number of relevant strain colonies had no remarkable increase in the Ames test with and without S₉ mixture, and the relationship of dose-response was also not found. The micronucleus rates and chromosome abnormality rates at all range of doses had no significant difference compared with the control group. At the dose of 500~5β000βμg/ml, the characteristic components extraction could not cause the increase of mutagenic rate of CHL (Chinese Hamster Lung Fibroblast, CHL) cells. It suggested that the extraction of characteristic components in Yunnan pu-erh tea has no mutagenicity for mouse．