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Antioxidants from natural sources have long been of interest to researchers. In this paper, taking the traditional Tibetan medicine <i>Ribes himalense</i> as an example, an integrated approach was used to identify and isolate its chemical composition with free-radical-scavenging properties from its ethanol extract. First, the ethanol extract of <i>Ribes himalense</i> was pretreated using polyamide medium-pressure liquid chromatography (polyamide-MPLC), and the target fraction (Fr4) was obtained. Then, a combined HPLC mode was utilized to purify antioxidants in Fr4 under the guidance of an online HPLC-1,1-diphenyl-2-picrylhydrazyl (HPLC-DPPH) activity screening system. Finally, three antioxidants (3-caffeoylquinic acid methyl ester, rutin, and myricetin-3′-α-L-rhamnopyranoside) were isolated, and this is the first report of their presence in <i>R. himalense</i>. Further molecular docking studies showed that the antioxidants exhibited good binding with HO-1, Nrf2, and iNOS. In conclusion, this comprehensive approach is capable of extracting high-purity antioxidants from trace fractions of <i>Ribes himalense</i> and holds promise for future applications in the exploration of the chemical compositions and bioactivity of natural products.