The use of medicinal herbs derivatives is an alternative to conventional medicine to treat diseases associated with oxidative stress. In this study we assessed the antioxidant capacity (AC) and the total phenolic (TP) and flavonoid content (FV) of 21 extracts obtained from commercially available supplies of native plants of Traslasierra valley, Cordoba; Hedeoma multiflorum, Minthostachys mollis, Lippia turbinata, Satureja parvifolia, Aloysia triphylla, Aloysia gratissima, Aloysia polystachya, Heterothalamus allienus, Xanthium spinosum, Gnaphalium gaudichaidianum, Flaveria bidentis, Hypericum connatum, Larrea divaricata, Aristolocchia macroura, Erythraea quitensis, Geoffroea decorticans, Solanum rutilum, Urtica dioica, Usnea gracilis, Anemia tomentosa and Lycopodium saururus. AC was assessed on the basis of different methods: The scavenging of stable free radicals ABTS and DPPH, the ability to reduce Fe +3 in the FRAP assay, and the capacity to inhibit the lipid peroxidation of copper-induced human plasma oxidation. All extracts were able to bleach the radicals in the range of 0.03 - 4.48 µmol of Trolox equivalent/mg dry extract. S. parvifolia and H. connatum extracts exhibited the highest scavenging activity for both, DPPH radical (1.48 and 1.77 µmol Tx eq/mg dry extract) and ABTS radical (3.20 and 4.48 µmol Tx eq./mg dry extract). S. parvifolia, L. divaricata and H. connatum showed the highest reducing capacity (8.89, 8.44 and 7.72 μmol eq. of ascorbic acid/mg dry extract) following by H. allienus and H. multiflorum. At 100 µg/mL, S. parvifolia and H. connatum also showed a very high capacity (> 85%) to inhibit Cu 2+ - induced human plasma peroxidation. E. quitensis, L.divaricata and H. multiflorum were also potent inhibitors of lipoperoxidation. There was a significant correlation between the TP and FV content and the AC (P<0.001). Taken together, our results suggest that the aqueous extracts of H. multiflorum, H. allienus, L. divaricata, H. connatum and S. parvifolia may be important sources for the isolation of compounds with potential use as pharmacological or nutritional tools..