DPPH (1,1-diphenyl-2-picryhydrazyl) radical scavenging assay was used to screen different fractions of Neo-Taraxacum siphonanthum ethanol extracts. The potent active fraction was isolated and purified by preparative high-speed counter-current chromatography (HSCCC) with a solvent system composed of n-hexane-n-butanol-water (3:4:7, v/v/v). The flow rate was 1.5mL/min and resolution speed was 800rpm. Three flavonoid glycosides with the purity over 99% were obtained and identified as luteolin- 3'-O--D-glucopyranoside (I), luteolin-7-O--D-glucopyranoside (II), and luteolin-4'-O--D-glucopyranoside (III) by ESI-MS, 1H NMR and 13C NMR analysis. Antioxidant activity of three flavonoid glycosides was assessed by DPPH assay, all of which showed potent activity.