Abstract: In this experiment,four anthocyanins were prepared by high-speed countercurrent chromatography using purple sweet potato,Lycium ruthenicum Murr.,black currant and mulberry for anthocyanin extract. Representative monomeric compounds extracted from the four samples were selected with more contents and medium molecular weights. The anthocyanin monomer compound of high purity was isolated by using methyl tert-butyl ether-n-butanol-acetonitrile-water-trifluoroacetic acid as solvent system. The flow rate was set at 5 mL/min and the rotation speed was 850 r/min. The content of anthocyanins and the main components were determined by spectrophotometry and HPLC-MS. The antioxidant activity was determined by DPPH radical,hydroxyl radical scavenging ability and total reducing power. The results showed that the representative components the four anthocyanin extracts were Peonidin-3-caffeoylferuloylsophoroside-5-glucoside,petunidin-3-O-(6-O-p-coumaryl)-rutinoside-5-O-glucoside,Cyanidin 3-rutinoside and Cyanidin——3-O-glucoside,respectively with good antioxidant activity in vitro.