Abstract:The in vitro antioxidant activities of different extractions of Spiranthes sinensis(Pers.)Ames were evaluated through DPPH and ABTS assays, and the total phenols contents were determined by Folin-Ciocalteu method. It was shown that all the different extraction parts of S. sinensis had significant in vitro antioxidant activities in a dose-dependent manner; The antioxidant activities and total phenols contents were both ordered as follows: ethyl acetate extraction>n-butanol extraction> petroleum ether extraction. The results showed that the in vitro antioxidant activities were positively correlated with the total phenols contents of different extraction parts of S. sinensis, the IC50 values of scavenging DPPH· and ABTS+· of ethyl acetate extraction part were (45.270±0.005) and (75.420±0.015) μg/mL, respectively, its total phenols content was (13.861±0.002)%.