Abstract: OBJECTIVE To investigate the anti-influenza A (H1N1) virus effect of organic?solvent extracts from Taraxaci Herba by neutralization test and proliferation inhibition test in vitro. METHODS After Taraxaci Herba was extracted by alcoholate, the alcoholate extracts of Taraxaci Herba were extracted by ethyl acetate, n-butyl alcohol, petroleum ether and water in turn. Cytopathogenic effect (CPE) of MDCK cell infection by influenza A (H1N1) virus was observed with the interference of Taraxaci Herba extract based on cell culture technique. The anti-influenza A (H1N1) virus effect of neutralization test and proliferation inhibition test of Taraxaci Herba extracts were observed by the hemagglutination titre test and Real time RT-PCR. RESULTS Anti-influenza A (H1N1) virus neutralization and proliferation inhibition effect of four Taraxaci Herba extracts were observed after 96 h of treatment. The results of neutralization test showed that hemagglutination titer of ethyl acetate extracts were 2-4 times lower than the control group. While the results of neutralization and proliferation inhibition test showed that hemagglutination titer of petroleum ether extract was 256 and 128 times lower than the control group, respectively. According to the results of Real time RT-PCR test, the inhibition ratio of ethyl acetate extract and petroleum ether extract were lower than the control group. After 96 h of treatment by petroleum ether extract, amplification inhibition rate of neutralization and proliferation inhibition test were 92.4% and 95.6% lower comparing to the control, respectively. CONCLUSION ethyl acetate and petroleum ether extract of Taraxaci Herba have anti-influenza A (H1N1) virus effects in vitro.