Objective: To compare the component of protein

vitamin C

vitamin E and volatile oil and superoside dismutase(SOD) activity of fresh and dried American ginseng and provide reference for reasonable application of American ginseng. Method: SDS-PAGE electrophoresis was carried out for protein analysis; UV spectrophotometry was used for determination of vitamin C and vitamin E; GC-MS was used for the analysis of volatile oil; SOD activity assay was detected with the methods of pyrogallol autoxidation and the data were analyzed by t-test. Result: The electrophoresis bands between fresh and dried American ginseng was different and the content of protein in fresh American ginseng was higher than dried one. The content of vitamin C and vitamin E

SOD activity assay in fresh American ginseng were significantly higher than dried one (P<0.01). The content and the kind of components of volatile oil were different and in fresh American ginseng was more than dried one. Conclusion: The component of protein

vitamin C

vitamin E

volatile oil

SOD activity in fresh American ginseng and dried one was different

which may be one of the reasons for the different of properties and efficacy.