In the present study, six total flavonoids extracts were prepared from Honey suckle, Walnut leaves, Withania Somnifera, Rhodiola rosea, Pomegranate bark, and Polygonum multiflorum. The total flavonoids content of six plant extracts were measured by aluminium nitrate-sodium nitrite colorimetry. The antioxidant activities of six extracts were compared by the detection methods of DPPH, ABTS and Fenton, and then the correlation of total flavonoids content was analyzed by Pearson. The results showed that the DPPH scavenging order was Honey suckle＞Walnut leaves＞W. Somnifera＞R. rosea＞P. multiflorum＞Pomegranate bark. The hydroxyl radical scavenging order was Honey suckle＞Walnut leaves＞W. Somnifera＞P. multiflorum＞Pomegranate bark＞Rhodiola rosea. The results showed that the ABTS⁺ scavenging order was Honey suckle＞Walnut leaves＞R. rosea＞W. Somnifera＞P. multiflorum＞Pomegranate bark. The free radical scavenging ability and flavonoids content of six kinds of extracts showed quantitative relationship. The correlation that the total flavonoid content and DPPH, ABTS⁺ was significantly positive, while with hydroxyl radical was not the same. The correlation coefficients above were 0.819, 0.848 and 0.791, respectively.